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A contact lens, or simply contact, is a thin lens placed directly on the surface of the eye. Contact lenses are ocular prosthetic devices used by over 150 million people worldwide,[1] and they can be worn to correct vision, for cosmetic, or therapeutic reasons.[2] In 2004, it was estimated that 125 million people worldwide use contact lenses, including 28 to 38 million in the United States.[3] In 2010, the worldwide market for contact lenses was estimated at $6.1 billion, while the US soft lens market was estimated at $2.1 billion.[4] Multiple analysts estimated that the global market for contact lenses would reach $11.7 billion by 2015.[4] As of 2010, the average age of contact lens wearers globally was 31 years old, and two-thirds of wearers were female.[5]
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People choose to wear contact lenses for many reasons.[6] Aesthetics and cosmetics are the main motivating factors for people who want to avoid wearing glasses or to change the appearance of their eyes.[7] Others wear contact lenses for functional or optical reasons. When compared with spectacles, contact lenses typically provide better peripheral vision, and do not collect moisture (from rain, snow, condensation etc.) or perspiration. This can make them preferable for sports and other outdoor activities. Contact lens wearers can also wear sunglasses, goggles, or other eyewear of their choice without having to fit them with prescription lenses or worry about compatibility with glasses. Additionally, there are conditions such as keratoconus and aniseikonia that are typically corrected better with contact lenses than with glasses.[8]
- 1History
- 2Types
- 2.1Functions
- 2.1.1Corrective contact lenses
- 2.2Materials
- 2.1Functions
- 4Prescriptions
- 6Usage
- 8In popular culture
History[edit]
V2 manual battery reset. Before using the battery, be sure to read the user's manual and cautions on handling thoroughly. For information on installing and removing the battery from equipment, thoroughly read the user's manual for the specific equipment.
Origins and first functional prototypes[edit]
Leonardo da Vinci is frequently credited with introducing the idea of contact lenses in his 1508 Codex of the eye, Manual D,[9] wherein he described a method of directly altering corneal power by either submerging the head in a bowl of water or wearing a water-filled glass hemisphere over the eye. Neither idea was practically implementable in da Vinci's time.[10]:9 He did not suggest his idea be used for correcting vision, as he was more interested in learning about the mechanisms of accommodation of the eye.[9]
Descartes proposed another idea in 1636—a glass tube filled with liquid placed in direct contact with the cornea. The protruding end was to be composed of clear glass, shaped to correct vision; however, the idea was impracticable since it made blinking impossible.
In 1801, Thomas Young made a pair of basic contact lenses based on Descartes' model. He used wax to affix water-filled lenses to his eyes, which neutralized its refractive power. He then corrected for it with another pair of lenses.[10]
However, like da Vinci's, Young's device was not intended to correct refraction errors. Sir John Herschel, in a footnote of the 1845 edition of the Encyclopedia Metropolitana, posed two ideas for the visual correction: the first 'a spherical capsule of glass filled with animal jelly',[11] and 'a mould of the cornea' that could be impressed on 'some sort of transparent medium'.[12] Though Herschel reportedly never tested these ideas, they were both later advanced by several independent inventors such as Hungarian Dallos with István Komáromy (1929),[clarification needed] who perfected a method of making molds from living eyes. This enabled the manufacture of lenses that, for the first time, conformed to the actual shape of the eye.
In 1888, German ophthalmologist Adolf Gaston Eugen Fick constructed and fitted the first successful contact lens.[13] While working in Zürich, he described fabricating afocalscleral contact shells, which rested on the less sensitive rim of tissue around the cornea, and experimentally fitting them; initially on rabbits, then on himself, and lastly on a small group of volunteers. These lenses were made from heavy blown glass and were 18–21 mm (0.71–0.83 in) in diameter. Fick filled the empty space between cornea and glass with a dextrose solution. He published his work, 'Contactbrille', in the journal Archiv für Augenheilkunde in March 1888.
Fick's lens was large and unwieldy, and could be worn only for a couple of hours at a time. August Müller in Kiel, Germany, corrected his own severe myopia with a more convenient blown-glass scleral contact lens of his own manufacture in 1888.[14]
Also in 1887, Louis J. Girard invented a similar scleral form of contact lens.[15] Blown-glass scleral lenses remained the only form of contact lens until the 1930s when Perspex/Plexiglas was developed, allowing plastic scleral lenses to be manufactured for the first time. In 1936, optometrist William Feinbloom introduced plastic in lenses, making them lighter and more convenient.[16] These lenses were a combination of glass and plastic. In 1939, Hungarian optometrist Dr István Györffy produced first fully plastic lenses.[17] Later, in 1940, German optometrist Heinrich Wöhlk produced fully plastic lenses too, based on experiments performed during the 1930s [18].
Corneal and rigid lenses (1949-1960s)[edit]
In 1949, the first 'corneal' lenses were developed.[19][20][21][22] These were much smaller than the original scleral lenses, as they sat only on the cornea rather than across all of the visible ocular surface, and could be worn up to 16 hours a day. Polymethyl methacrylate (PMMA) corneal lenses became the first contact lenses to have mass appeal through the 1960s, as lens designs became more sophisticated with improving manufacturing technology.[citation needed] On October 18, 1964, in a television studio in Washington, D.C., Lyndon Baines Johnson became the first President in the history of the United States to appear in public wearing contact lenses, under the supervision of Dr. Alan Isen, who developed the first commercially viable soft-contact lenses in the United states.[23][24][25]
Early corneal lenses of the 1950s and 1960s were relatively expensive and fragile, resulting in the development of a market for contact lens insurance. Replacement Lens Insurance, Inc. (now known as RLI Corp.) phased out its original flagship product in 1994 after contact lenses became more affordable and easier to replace.[citation needed]
Gas permeable and soft lenses (1959-current)[edit]
One major disadvantage of PMMA lenses is that they allow no oxygen to get through to the conjunctiva and cornea, causing a number of adverse and potentially serious clinical effects. By the end of the 1970s and through the 1980s and 1990s, a range of oxygen-permeable but rigid materials were developed to overcome this problem. Chemist Norman Gaylord played a prominent role in the development of these new oxygen-permeable contact lenses.[26] Collectively, these polymers are referred to as rigid gas permeable or RGP materials or lenses. Though all the above contact lens types—sclerals, PMMAs and RGPs—could be correctly referred to as 'rigid' or 'hard', the latter term is now used to the original PMMAs, which are still occasionally fitted and worn, whereas 'rigid' is a generic term for all these lens types; thus hard lenses (PMMAs) are a subset of rigid contact lenses. Occasionally, the term 'gas permeable' is used to describe RGPs, which is somewhat misleading as soft contact lenses are also gas permeable in that they allow oxygen to get through to the ocular surface.
The principal breakthrough in soft lenses was made by Czech chemists Otto Wichterle and Drahoslav Lím, who published their work 'Hydrophilic gels for biological use' in the journal Nature in 1959.[27] In 1965, National Patent Development Corporation (NPDC) bought the American rights to produce the lenses and then sublicensed the rights to Bausch & Lomb, which started to manufacture them in the United States.[28] The Czech scientists' work led to the launch of the first soft (hydrogel) contact lenses in some countries in the 1960s and the first approval of the Soflens material by the US Food and Drug Administration (FDA) in 1971. These soft lenses were soon prescribed more often than rigid ones, due to the immediate and much greater comfort (rigid lenses require a period of adaptation before full comfort is achieved). Polymers from which soft lenses are manufactured improved over the next 25 years, primarily in terms of increasing oxygen permeability, by varying the ingredients. In 1972, British optometrist Rishi Agarwal was the first to suggest disposable soft contact lenses.[29][30]
In 1998, the first silicone hydrogel contact lenses were released by Ciba Vision in Mexico. These new materials encapsulated the benefits of silicone—which has extremely high oxygen permeability—with the comfort and clinical performance of the conventional hydrogels that had been used for the previous 30 years. These contact lenses were initially advocated primarily for extended (overnight) wear, although more recently, daily (no overnight) wear silicone hydrogels have been launched.
In a slightly modified molecule, a polar group is added without changing the structure of the silicone hydrogel. This is referred to as the Tanaka monomer because it was invented and patented by Kyoichi Tanaka of Menicon Co. of Japan in 1979. Second-generation silicone hydrogels, such as galyfilcon A (Acuvue Advance, Vistakon) and senofilcon A (Acuvue Oasys, Vistakon), use the Tanaka monomer. Vistakon improved the Tanaka monomer even further and added other molecules, which serve as an internal wetting agent.[31]
Comfilcon A (Biofinity, CooperVision) was the first third-generation polymer. Its patent claims that the material uses two siloxy macromers of different sizes that, when used in combination, produce very high oxygen permeability (for a given water content). Enfilcon A (Avaira, CooperVision) is another third-generation material that is naturally wettable; its water content is 46%.[31]
Types[edit]
Contact lenses are classified in many different ways: by their primary function, material, wear schedule (how long a lens can be worn), and replacement schedule (how long before a lens needs to be discarded).
Functions[edit]
Corrective contact lenses[edit]
Corrective contact lenses are designed to improve vision, most commonly by correcting refractive error. This is done by directly focusing light so it enters the eye with the proper power for clear vision.
A spherical contact lens bends light evenly in every direction (horizontally, vertically, etc.). They are typically used to correct myopia and hypermetropia. A toric contact lens has a different focusing power horizontally than vertically, and as a result can correct for astigmatism. Some spherical rigid lenses can also correct for astigmatism. Because a toric lens must have the proper orientation to correct for a person's astigmatism, such a lens must have additional design characteristics to prevent it from rotating away from the ideal alignment. This can be done by weighting the bottom of the lens or by using other physical characteristics to rotate the lens back into position. Some toric contact lenses have marks or etchings that can assist the eye doctor or the user in fitting the lens. The first disposable toric contact lenses were introduced in 2000 by Vistakon.
Correction of presbyopia (a need for a reading prescription different from the prescription needed for distance) presents an additional challenge in the fitting of contact lenses. Two main strategies exist: multifocal lenses and monovision.
Multifocal contact lenses (e.g. bifocals or progressives) are comparable to spectacles with bifocals or progressive lenses because they have multiple focal points. Multifocal contact lenses are typically designed for constant viewing through the center of the lens, but some designs do incorporate a shift in lens position to view through the reading power (similar to bifocal glasses).
Monovision[32] is the use of single-vision lenses (one focal point per lens) to focus an eye (typically the dominant one) for distance vision and the other for near work. The brain then learns to use this setup to see clearly at all distances. A technique called modified monovision uses multifocal lenses and also specializes one eye for distance and the other for near, thus gaining the benefits of both systems. Care is advised for persons with a previous history of strabismus and those with significant phorias, who are at risk of eye misalignment under monovision.[33] Studies have shown no adverse effect to driving performance in adapted monovision contact lens wearers.[34]
Alternatively, a person may simply wear reading glasses over their distance contact lenses.
Other types of vision correction[edit]
For those with certain color deficiencies, a red-tinted 'X-Chrom' contact lens may be used. Although such a lens does not restore normal color vision, it allows some color-blind people to distinguish colors better.[35][36] Red-filtering contact lenses can also be an option for extreme light sensitivity in some visual deficiencies such as achromatopsia.[37]
ChromaGen contact lenses have been used and shown to have some limitations with vision at night although otherwise producing significant improvements in color vision.[38] An earlier study showed very significant improvements in color vision and patient satisfaction.[39]
Later work that used these ChromaGen lenses with dyslexics in a randomised, double-blind, placebo controlled trial showed highly significant[clarification needed] improvements in reading ability over reading without the lenses.[40] This system has been granted FDA approval for use in the United States.[citation needed]
Magnification is another area being researched for future contact lens applications.[41] Embedding of telescopic lenses and electronic components suggests that future uses of contact lenses may become extremely diverse.
Cosmetic contact lenses[edit]
A cosmetic contact lens is designed to change the appearance of the eye. These lenses may also correct refractive error. Although many brands of contact lenses are lightly tinted to make them easier to handle, cosmetic lenses worn to change eye color are far less common, accounting for only 3% of contact lens fits in 2004.[42]
In the United States, the FDA labels non-corrective cosmetic contact lenses as decorative contact lenses. Like any contact lens, cosmetic lenses carry risks of mild to serious complications, including ocular redness, irritation and infection.[43]
Due to their medical nature, colored contact lenses, similar to regular ones, are illegal to purchase in the United States without a valid prescription. Those with perfect vision can buy color contacts for cosmetic reasons, but they still need their eyes to be measured for a 'plano' prescription, meaning one with zero vision correction. This is for safety reasons so the lenses will fit the eye without causing irritation or redness.[44]
Some colored contact lenses completely cover the iris, thus dramatically changing eye colour. Other colored contact lenses merely tint the iris, highlighting its natural colour.[45] A new trend in Japan, South Korea and China is the circle contact lens, which extend the appearance of the iris onto the sclera by having a dark tinted area all around. The result is an appearance of a bigger, wider iris, a look reminiscent of dolls' eyes.[46]
One of the drawbacks of cosmetic lenses is not knowing how they will look before physically trying them on. This has led to an industry where lens retailers are heavily influenced by cutting edge digital fashion technology, specifically the Virtual Dressing Room technology. Virtual Dressing Room technology offers users the option to upload a photo so they can virtually try on different lenses and experience how they will look before committing to a purchase. Examples of retailers that currently offer this technology are Freshlook Color Studios and Colorful Eyes.[47][48]
Cosmetic lenses can have more direct medical applications. For example, some contact lenses can restore the appearance and, to some extent the function, of a damaged or missingiris.
Therapeutic scleral lenses[edit]
A scleral lens is a large, firm, transparent, oxygen-permeable contact lens that rests on the sclera and creates a tear-filled vault over the cornea. The cause of this unique positioning is usually relevant to a specific patient whose cornea is too sensitive to support the lens directly. Scleral lenses may be used to improve vision and reduce pain and light sensitivity for people suffering from disorders or injuries to the eye, such as severe dry eye syndrome (Kerotanconjuctivis sicca), microphthalmia, keratoconus, corneal ectasia, Stevens–Johnson syndrome, Sjögren's syndrome, aniridia, neurotrophic keratitis (aneasthetic corneas), complications post-LASIK, high order Aberrations of the eye, complications post-corneal transplant and pellucid degeneration. Injuries to the eye such as surgical complications, distorted corneal implants, as well as chemical and burn injuries also may be treated with scleral lenses.[49]
Therapeutic soft lenses[edit]
Soft lenses are often used in the treatment and management of non-refractive disorders of the eye. A bandage contact lens allows the patient to see[50] while protecting an injured or diseased cornea[51] from the constant rubbing of blinking eyelids, thereby allowing it to heal.[52] They are used in the treatment of conditions including bullous keratopathy, dry eyes, corneal abrasions and erosion, keratitis, corneal edema, descemetocele, corneal ectasis, Mooren's ulcer, anterior corneal dystrophy, and neurotrophic keratoconjunctivitis.[53] Contact lenses that deliver drugs to the eye have also been developed.[54]
Materials[edit]
Rigid lenses[edit]
Glass lenses were never comfortable enough to gain widespread popularity. The first lenses to do so were those made from polymethyl methacrylate (PMMA or Perspex/Plexiglas), now commonly referred to as 'hard' lenses. Their main disadvantage is they do not allow oxygen to pass through to the cornea, which can cause a number of adverse, and often serious, clinical events. Starting in the late 1970s, improved rigid materials which were oxygen-permeable were developed. Contact lenses made from these materials are called rigid gas permeable lenses or 'RGPs'.
A rigid lens is able to cover the natural shape of the cornea with a new refracting surface. This means that a spherical rigid contact lens can correct corneal astigmatism. Rigid lenses can also be made as a front-toric, back-toric, or bitoric. Rigid lenses can also correct corneas with irregular geometries, such as those with keratoconus or post surgical ectasias. In most cases, patients with keratoconus see better through rigid lenses than through glasses. Rigid lenses are more chemically inert, allowing them to be worn in more challenging environments than soft lenses.[citation needed]
Soft lenses[edit]
Soft lenses are more flexible than rigid lenses, and can be gently rolled or folded without damaging the lens. While rigid lenses require a period of adaptation before comfort is achieved, new soft lens wearers typically report lens awareness rather than pain or discomfort.
Hydrogel lenses rely on their water content to transmit oxygen through the lens to the cornea. As a result, higher water content lenses allowed more oxygen to the cornea. In 1998, silicone hydrogel, or Si-hy lenses became available. These materials have both the extremely high oxygen permeability of silicone and the comfort and clinical performance of the conventional hydrogels. Because silicone allows more oxygen permeability than water, oxygen permeability of silicone hydrogels is not tied to the lenses' water content. Lenses have now been developed with so much oxygen permeability that they are approved for overnight wear (extended wear). Lenses approved for daily wear are also available in silicone hydrogel materials.[55]
Disadvantages of silicone hydrogels are that they are slightly stiffer and the lens surface can be hydrophobic, thus less 'wettable' – factors that can influence comfort of lens use. New manufacturing techniques and changes to multipurpose solutions have minimized these effects. A surface modification process called plasma coating alters the lens surface's hydrophobic nature. Another technique incorporates internal rewetting agents to make the lens surface hydrophilic. A third process uses longer backbone polymer chains that results in less cross linking and increased wetting without surface alterations or additive agents.
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Current brands of soft lenses are either traditional hydrogel or silicone hydrogel. Because of drastic differences in oxygen permeability, replacement schedule, and other design characteristics, it is very important to follow the instructions of the eye care professional prescribing the lenses.
Hybrid[edit]
A small number of hybrid lenses exist. Typically these contact lenses consist of a rigid center and a soft 'skirt'. A similar technique is the 'piggybacking' of a smaller, rigid lens on the surface of a larger, soft lens. These techniques are often chosen to give the vision correction benefits of a rigid lens and the comfort of a soft lens.[56]
Wear schedule[edit]
A 'daily wear' (DW) contact lens is designed to be worn for one day and removed before sleeping. An 'extended wear' (EW) contact lens is designed for continuous overnight wear, typically for up to 6 consecutive nights. Newer materials, such as silicone hydrogels, allow for even longer wear periods of up to 30 consecutive nights; these longer-wear lenses are often referred to as 'continuous wear' (CW). EW and CW contact lenses can be worn overnight because of their high oxygen permeability. While awake, the eyes are mostly open, allowing oxygen from the air to dissolve into the tears and pass through the lens to the cornea. While asleep, oxygen is supplied from the blood vessels in the back of the eyelid. A lens hindering passage of oxygen to the cornea causes corneal hypoxia which can result in serious complications, such as corneal ulcer that, if left untreated, can permanently decrease vision. EW and CW contact lenses typically allow for a transfer of 5–6 times more oxygen than conventional softs, allowing the cornea to remain healthy, even with closed eyelids.
Wearing lenses designed for daily wear overnight has an increased risk for corneal infections, corneal ulcers and corneal neovascularization—this latter condition, once it sets in, cannot be reversed and will eventually spoil vision acuity through diminishing corneal transparency. The most common complication of extended wear is giant papillary conjunctivitis (GPC), sometimes associated with a poorly fitting contact lens.
Replacement schedule[edit]
Contact lenses are often categorized by their replacement schedule. Single use lenses (called 1-day or daily disposables) are discarded after one use. Because they do not have to stand up to the wear and tear of repeated uses, these lenses can be made thinner and lighter, greatly improving their comfort. Lenses replaced frequently gather fewer deposits of allergens and germs, making these lenses preferable for patients with ocular allergies or for those who are prone to infection. Single-use lenses are also useful for people who wear contact lenses infrequently, or when losing a lens is likely or not easily replaced (such as when on vacation). They are also considered useful for children because cleaning or disinfecting is not needed, leading to improved compliance.
Other disposable contact lenses are designed for replacement every two or four weeks. Quarterly or annual lenses, which used to be very common, are now much less so. Rigid gas permeable lenses are very durable and may last for several years without the need for replacement. PMMA hards were very durable and were commonly worn for 5 to 10 years, but had several drawbacks.
Lenses with different replacement schedules can be made of the same material. Although the materials are alike, differences in the manufacturing processes determine if the resulting lens will be a 'daily disposable' or one recommended for two or four week replacement. However, sometimes manufacturers use absolutely identical lenses and just repackage them with different labels.[57][58]
Manufacturing[edit]
Typically, soft contact lenses are mass-produced, while rigids are custom-made to exact specifications for the individual patient.
- Spin-cast lenses – A soft lens manufactured by whirling liquid silicone in a revolving mold at high speed.[59]
- Diamond turning – This type is cut and polished on a CNC lathe.[59] The lens starts out as a cylindrical disk held in the jaws of the lathe that is equipped with an industrial-grade diamond as the cutting tool. The CNC lathe may turn at nearly 6000 RPM as the cutter removes the desired amount of material from the inside of the lens. The concave (inner) surface of the lens is then polished with some fine abrasive paste, oil, and a small polyester cotton ball turned at high speeds. To hold the delicate lens in reverse manner, wax is used as an adhesive. The lens' convex (outer) surface is thus cut and polished by the same process. This method can be used to shape rigid as well as soft lenses. In the case of softs, the lens is cut from a dehydrated polymer that is rigid until water is reintroduced.
- Molded – Molding is used to manufacture some brands of soft contact lenses. Rotating molds are used and the molten material is added and shaped by centripetal forces. Injection molding and computer control are also used to create nearly perfect lenses.[60] The lens is kept moist throughout the entire molding process and is never dried and rehydrated.
Many companies make contact lenses. In the United States, there are five major manufacturers:[61]
- Johnson & Johnson; maker of Acuvue lenses.
- The Cooper Companies: through its CooperVision
- Alcon.
- Bausch Health: through its Bausch & Lomb subsidiary.
- X-Cel Specialty Contacts; maker of Westcon lenses.
Prescriptions[edit]
The parameters specified in a contact lens prescription may include:
- Material / Brand name
- Base curve radius (BC, BCR)
- Diameter (D, OAD)
- Power in diopters
- Center thickness (CT)
Prescriptions for contact lenses and glasses may be similar, but are not interchangeable. Prescribing of contact lenses is usually restricted to various combinations of ophthalmologists, optometrists and opticians. An eye examination is needed to determine an individual's suitability for contact lens wear. This typically includes a refraction to determine the proper power of the lens and an assessment of the health of the eye's anterior segment. Many eye diseases prohibits contact lens wear, such as active infections, allergies, and dry eye.[62]Keratometry is especially important in the fitting of rigid lenses.
United States[edit]
Contact lenses are prescribed by ophthalmologists, optometrists, or specially licensed opticians under the supervision of an eye doctor. Contact lenses can typically be ordered at the office that conducts the eye exam and fitting. The Fairness to Contact Lens Consumers Act[63] gives consumers the right to obtain a copy of their contact lens prescription, allowing them to fill it at the lens provider of their choice.
Complications[edit]
Contact lenses are generally safe as long as they are used correctly. Complications from contact lens wear affect roughly 5% of wearers yearly.[64] Factors leading to eye damage varies,[65] and improper use of a contact lens may affect the eyelid, the conjunctiva, and, most of all, the whole structure of the cornea.[64] Poor lens care can lead to infections by various microorganisms including bacteria, fungi, and Acanthamoeba (Acanthamoeba keratitis).
Many complications arise when contact lenses are worn not as prescribed (improper wear schedule or lens replacement). Sleeping in lenses not designed or approved for extended wear is a common cause of complications. Many people go too long before replacing their contacts, wearing lenses designed for 1, 14, or 30 days of wear for multiple months or years. While this does save on the cost of lenses, it risks permanent damage to the eye and even loss of sight.
One of the major factors that causes complications is that the contact lens is an oxygen barrier. The cornea needs a constant supply of oxygen to remain completely transparent and function as it should; it normally gets that oxygen from the surrounding air while awake, and from the blood vessels in the back of the eyelid while asleep. The most prominent risks associated with long-term, chronic low oxygen to the cornea include corneal neovascularization, increased epithelial permeability, bacterial adherence, microcysts, corneal edema, endothelial polymegethism, dry eye and potential increase in myopia.[66] That is why much of the research into the latest soft and rigid contact lens materials has centered on improving oxygen transmission through the lens.
Mishandling of contact lenses can also cause problems. Corneal abrasions can increase the chances of infection.[67] When combined with improper cleaning and disinfection of the lens, a risk of infection further increases. Decreased corneal sensitivity after extended contact lens wear may cause a patient to miss some of the earliest symptoms of such complications.[68]
The way contact lenses interact with the natural tear layer is a major factor in determining lens comfort and visual clarity. People suffering from dry eyes are particularly vulnerable to discomfort and episodes of brief blurry vision. Proper lens selection can minimize these effects.
Long-term wear (over five years) of contact lenses may 'decrease the entire corneal thickness and increase the corneal curvature and surface irregularity.'[69] Long-term wear of rigid contacts is associated with decreased corneal keratocyte density[70] and increased number of epithelialLangerhans cells.[71]
All contact lenses sold in the United States are studied and approved as safe by the FDA when specific handling and care procedures, wear schedules, and replacement schedules are followed.
Usage[edit]
Before touching the contact lens or the eye, it is important to wash hands thoroughly with soap and rinse well. Soaps containing moisturizers or allergens should be avoided as these can cause eye irritation.[72] Drying of hands using towels or tissues before handling contact lenses can transfer lint (fluff) to the hands and, subsequently, to the lenses, causing irritation upon insertion. Towels, unless freshly laundered on high temperature wash, are frequently contaminated with large quantities of bacteria and, as such, should be avoided when handling lenses. Dust, lint and other debris may collect on the outside of contact lenses. Again, hand contact with this material, before handling contact lenses, may transfer it to the lenses themselves. Rinsing the case under a source of clean running water, before opening it, can help alleviate this problem. Next the lens should be removed from its case and inspected for defects (e.g. splits, folds, lint). A 'gritty' or rough appearance to the lens surface may indicate that a considerable quantity of proteins, lipids and debris has built up on it and that additional cleaning is required; this is often accompanied and felt by unusually high irritation upon insertion.
Make sure the soft lens is not inserted inside-out. Edge of a lens turned inside out has a different appearance, especially when the lens is slightly folded. Insertion of an inside-out lens for a brief time (less than one minute) should not cause any damage to the eye. Some brands of lenses have markings (e.g. numbers) on the rim that make it easier to tell the front of the lens from the back.
The technique for removing or inserting a contact lens varies depending upon whether the lens is soft or rigid. There are many subtle variations to insertion and removal techniques. Because of differences in anatomy, manual dexterity, and visual limitations, every person must find the technique that works best for them. In all cases, the insertion and removal of lenses requires some training and practice on part of the user.
Insertion[edit]
Contact lenses are typically inserted into the eye by placing them on the pad of the index or middle finger with the concave side upward and then using that finger to place the lens on the eye. Rigid lenses should be placed directly on the cornea. Soft lenses may be placed on the sclera (white of the eye) and then slid into place. Another finger of the same hand, or a finger of the other hand, is used to keep the eye wide open. Alternatively, the user may close their eyes and then look towards their nose, sliding the lens into place over the cornea. Problems may arise if the lens folds, turns inside-out, slides off the finger prematurely, or adheres more tightly to the finger than the eye surface. A drop of solution may help the lens adhere to the eye.
When the lens first contacts the eye, it should be comfortable. By making sure that particular attention is given to the eyelid margins for the presence of inflammation and signs of debris in the lashes, wearing contact lenses should be easy.[73] A brief period of irritation may occur, caused by a difference in pH and/or salinity between that of the lens solution and the tear.[74][75] This discomfort fades quickly as the solution drains away and is replaced by the natural tears. However, if irritation persists, the cause could be a dirty, damaged, or inside-out lens. Removing and inspecting it for damage and proper orientation, and re-cleaning if necessary, should correct the problem. If discomfort continues, the lens should not be worn. In some cases, taking a break from lens wear for a day may correct the problem. In case of severe discomfort, or if it does not resolve by the next day, the person should be seen as soon as possible by an eye doctor to rule out potentially serious complications.
Removal[edit]
Removing contact lenses incorrectly can result in damage to the lens and injury to the eye, so certain precautions must be taken. Rigid contact lenses can best be removed by pulling the eyelid tight and then blinking, whereupon the lens drops out. With one finger on the outer corner of the eyelids, or lateral canthus, the person stretches the eyelids towards the ear; the increased tension of the eyelid margins against the edge of lens allows the blink to break the capillary action that adheres the lens to the eye. The other hand is typically cupped underneath the eye to catch the lens as it drops out. For soft lenses, which have a stronger adherence to the eye surface, this technique is less suitable.
A soft contact lens may be removed by pinching the edge between the thumb and index finger. Moving the lens off the cornea first can improve comfort during removal and reduce risk of scratching the cornea with a fingernail. It is also possible to push or pull a soft lens far enough to the side or bottom of the eyeball to get it to fold then fall out, without pinching and thereby damaging it. If these techniques are used with a rigid lens, it may scratch the cornea.
There are also small tools specifically for removing lenses. Usually made of flexible plastic, they resemble small tweezers, or plungers that suction onto the front of the lens. Typically, these tools are used only with rigid lenses. Extreme care must be exercised when using mechanical tools or fingernails to insert or remove contact lenses.
Care[edit]
Lens care varies depending on material and wear schedule. Daily disposables are discarded after a single use and thus require no cleaning. Other lenses need regular cleaning and disinfecting to prevent surface coating and infections.
There are many ways to clean and care for contact lenses, typically called care systems or lens solutions:
- Multipurpose solutions
- Multipurpose solutions are the most common method for rinsing, disinfecting, cleaning, and storing soft lenses. In 2002, concerns were raised that multipurpose solutions are not effective at disinfecting Acanthamoeba from the lens.[76] In May 2007, one brand of multipurpose solution was recalled due to a cluster of Acanthamoeba infections.[77][78] Since then, studies showed that multipurpose solutions are ineffective against Acanthamoebae.[79][80][81] The latest multipurpose solutions also contain ingredients that improve the surface wetability and comfort of silicone hydrogel lenses.[82][citation needed]
- Hydrogen peroxide can be used to disinfect contact lenses.[83] Care should be taken not to get hydrogen peroxide in the eye because it is very painful and irritating. With 'two-step' products, the hydrogen peroxide must be rinsed away with saline before the lenses may be worn. 'One-step' systems allow the hydrogen peroxide to react completely, becoming pure water. Thus 'one-step' hydrogen peroxide systems do not require the lenses to be rinsed before insertion, provided the solution has been given enough time to react. An exposure time of 2-3 hours to 3% H
2O
2 (non neutralized solution) is sufficient to kill bacteria, HIV, fungi, and Acanthamoeba.[84][85] This can be achieved by using a 'two-step' product or a 'one-step' tablet system if the catalytic tablet isn't added before 2-3 hours.[85] However, the 'one-step' catalytic disk systems are not effective against Acanthamoeba.[85]
- Hydrogen peroxide can be used to disinfect contact lenses.[83] Care should be taken not to get hydrogen peroxide in the eye because it is very painful and irritating. With 'two-step' products, the hydrogen peroxide must be rinsed away with saline before the lenses may be worn. 'One-step' systems allow the hydrogen peroxide to react completely, becoming pure water. Thus 'one-step' hydrogen peroxide systems do not require the lenses to be rinsed before insertion, provided the solution has been given enough time to react. An exposure time of 2-3 hours to 3% H
- Enzymatic cleaner – Used for cleaning protein deposits off lenses, usually weekly, if the daily cleaner is not sufficient. Typically, this cleaner is in tablet form.
- Ultraviolet, vibration, or ultrasonic devices – Used to both disinfect and clean CLs. The lenses are inserted inside the portable device (running on batteries and/or plug-in) for 2 to 6 minutes during which both the microorganisms and protein build-up are thoroughly cleaned. These devices are not usually available in optic retailers but are in other stores.[86][87][88]
- Saline solution
- Sterile saline is used for rinsing the lens after cleaning and preparing it for insertion. Saline solutions do not disinfect, so it must be used in conjunction with some type of disinfection system. One advantage to saline is that it cannot cause an allergic response, so it is well suited for individuals with sensitive eyes or strong allergies.
- Daily cleaner
- Used to clean lenses on a daily basis. A few drops of cleaner are applied to the lens while it rests in the palm of the hand; the lens is rubbed for about 20 seconds with a clean fingertip (depending on the product) on each side. Lens must then be rinsed. This system is commonly used to care for rigid lenses.
Aside from cleaning the contact lenses, it is highly advised to also clean the cases to avoid any possible infection. Replacing the case monthly, and storing it in a clean and safe environment is also recommended.[89]
Contact lenses can be mechanically cleaned of more substantial protein, lipid and debris build up by rubbing them between the clean pad of a finger and the palm of a hand, using a small amount of cleaning fluid as a lubricant. However, this method does not sterilize the lenses and so should be performed only before a full sterilization cycle (e.g. when putting the contact lens away at night).
Some products must be used only with certain types of contact lenses. Water alone will not at all disinfect the lens, and can lead to lens contamination causing potentially irreparable harm to the eye.
Contact lens solutions often contain preservatives such as benzalkonium chloride and benzyl alcohol. Preservative-free products usually have shorter shelf lives, but are better suited for individuals with an allergy or sensitivity to a preservative. In the past, thiomersal was used as a preservative. In 1989, thiomersal was responsible for about 10% of problems related to contact lenses.[90] As a result, most products no longer contain thiomersal.
Current research[edit]
Contact lens sensors to monitor the ocular temperature were recently demonstrated.[91] A large segment of current contact lens research is directed towards the treatment and prevention of conditions resulting from contact lens contamination and colonization by foreign organisms. Clinicians tend to agree that the most significant complication of contact lens wear is microbial keratitis and that the most predominant microbial pathogen is Pseudomonas aeruginosa.[92] Other organisms are also major causative factors in bacterial keratitis associated with contact lens wear, although their prevalence varies across different locations. These include both the Staphylococcus species (aureus and epidermidis) and the Streptococcus species, among others.[93][94] Microbial keratitis is a serious focal point of current research due to its potentially devastating effect on the eye, including severe vision loss.[95]
One specific research topic of interest is how microbes such as Pseudomonas aeruginosa invade the eye and cause infection. Although the pathogenesis of microbial keratitis is not well understood, many different factors have been investigated. One group of researchers showed that corneal hypoxia exacerbated Pseudomonas binding to the corneal epithelium, internalization of the microbes, and induction of the inflammatory response.[96] One way to alleviate hypoxia is to increase the amount of oxygen transmitted to the cornea. Although silicone-hydrogel lenses almost eliminate hypoxia in patients due to their very high levels of oxygen transmissibility,[97] they also seem to provide a more efficient platform for bacterial contamination and corneal infiltration than other conventional hydrogel soft contact lenses. A recent study showed that Pseudomonas aeruginosa and Staphylococcus epidermis adhere much more strongly to unworn silicone hydrogel contact lenses than conventional hydrogel lenses and that adhesion of Pseudomonas aeruginosa was 20 times stronger than that of Staphylococcus epidermidis.[98] This might partly explain why Pseudomonas infections are the most predominant. However, another study conducted with worn and unworn silicone and conventional hydrogel contact lenses showed that worn silicone contact lenses were less prone to Staphylococcus epidermidis colonization than conventional hydrogel lenses.[99]
Another important area of contact lens research deals with patient compliance. Compliance is a major issue[100] pertaining to the use of contact lenses because patient noncompliance often leads to contamination of the lens, storage case, or both.[101][102][103] However, careful users can extend the wear of lenses through proper handling: there is, unfortunately, no disinterested research on the issue of 'compliance' or the length of time a user can safely wear a lens beyond its stated use. The introduction of multipurpose solutions and daily disposable lenses have helped to alleviate some of the problems observed from inadequate cleaning but new methods of combating microbial contamination are currently being developed. A silver-impregnated lens case has been developed which helps to eradicate any potentially contaminating microbes that come in contact with the lens case.[104] Additionally, a number of antimicrobial agents are being developed that have been embedded into contact lenses themselves. Lenses with covalently attached selenium molecules have been shown to reduce bacterial colonization without adversely affecting the cornea of a rabbit eye[105] and octyl glucoside used as a lens surfactant significantly decreases bacterial adhesion.[106] These compounds are of particular interest to contact lens manufacturers and prescribing optometrists because they do not require any patient compliance to effectively attenuate the effects of bacterial colonization.
A recent area of research is in the field of bionic lenses. These are visual displays that include built-in electric circuits and light-emitting diodes and can harvest radio waves for their electric power. Bionic lenses can display information beamed from a mobile device overcoming the small display size problem. The technology involves embedding nano and microscale electronic devices in lenses. These lenses will also need to have an array of microlenses to focus the image so that it appears suspended in front of the wearer’s eyes. The lens could also serve as a head-up display for pilots or gamers.[107]
Drug administration through contact lenses is also becoming an area of research. One application is a lens that releases anesthesia to the eye for post-surgery pain relief, especially after PRK (photorefractive keratectomy) in which the healing process takes several days. One experiment shows that silicone contact lenses that contain vitamin E deliver pain medication for up to seven days compared with less than two hours in usual lenses.[107]
Another study of the usage of contact lens is aimed to address the issue of macular degeneration (AMD or age-related macular degeneration). An international collaboration of researchers was able to develop a contact lens that can shift between magnified and normal vision. Previous solutions to AMD included bulky glasses or surgical implants. But the development this new contact lens, which is made of polymethyl methacrylate, could offer an unobtrusive solution.[108]
In popular culture[edit]
Films[edit]
One of the earliest known motion pictures to introduce the use of contact lenses as a make-up artist's device for enhancing the eyes was by the innovative actor Lon Chaney in the 1926 film The Road to Mandalay to create the effect of a character who had a blind eye.[109] Dr. Rueben Greenspoon applied them to Orson Welles for the film Citizen Kane in 1940. In the 1950s, contact lenses were starting to be used in British color horror films. An early example of this is the British actor Christopher Lee as the Dracula character in the 1958 color horror film Dracula, which helped to emphasize his horrific looking black pupils and red bloodshot eyes. Tony Curtis wore them in the 1968 film The Boston Strangler. Contact lenses were also used to better emphasize the sinister gaze of the demonic characters in 1968's Rosemary's Baby and 1973's The Exorcist. Colored custom-made contact lenses are now standard makeup for a number of special effects-based movies.[110]
See also[edit]
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- ^Amos CF, George MD (2006). 'Clinical and laboratory testing of a silver-impregnated lens case'. Cont Lens Anterior Eye. 29 (5): 247–55. doi:10.1016/j.clae.2006.09.007. PMID17084102.
- ^Mathews SM, Spallholz JE, Grimson MJ, Dubielzig RR, Gray T, Reid TW (2006). 'Prevention of bacterial colonization of contact lenses with covalently attached selenium and effects on the rabbit cornea'. Cornea. 25 (7): 806–14. doi:10.1097/01.ico.0000224636.57062.90. PMID17068458.
- ^Santos L; Rodrigues D; Lira M; Oliveira R; Oliveira Real, ME; Vilar EY; Azeredo J (2007). 'The effect of octylglucoside and sodium cholate in Staphylococcus epidermidis and Pseudomonas aeruginosa adhesion to soft contact lenses'. Optom Vis Sci. 84 (5): 429–34. doi:10.1097/opx.0b013e318058a0cc. PMID17502827.
- ^ ab'Contacts Release Anesthesia to Eyes of Post-Surgery Patients'. Archived from the original on 21 April 2013. Retrieved 4 April 2013.
- ^'First Ever Switchable Telescopic Contact Lens'. Retrieved 23 March 2018.
- ^Klepper, Robert K. (2005). Silent Films, 1877–1996: A Critical Guide to 646 Movies. McFarland. p. 373.
- ^Yazigi, Monique P. (17 July 1994). 'On Film, Them There Eyes Are Often Contact Lenses'. New York Times.
Further reading[edit]
- Efron, Nathan (2002). Contact Lens Practice. Elsevier Health Sciences. ISBN0-7506-4690-X.
- Heitz, Robert (2003, 2005 and 2014). 'The History of Contact Lenses'. In: Julius Hirschberg, History of Ophthalmology, vols. 11/3a, 11/3b, and 11/3c. Ostend, Belgium: Wayenborgh Publishing; Paraguay: Piribebuy. ISBN978-90-6299-463-2.
External links[edit]
Wikimedia Commons has media related to Contact lens. |
- Focusing on Contact Lens Safety from Food and Drug Administration
Property law |
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Property, in the abstract, is what belongs to or with something, whether as an attribute or as a component of said thing. In the context of this article, it is one or more components (rather than attributes), whether physical or incorporeal, of a person's estate; or so belonging to, as in being owned by, a person or jointly a group of people or a legal entity like a corporation or even a society. Depending on the nature of the property, an owner of property has the right to consume, alter, share, redefine, rent, mortgage, pawn, sell, exchange, transfer, give away or destroy it, or to exclude others from doing these things,[1][2][3] as well as to perhaps abandon it; whereas regardless of the nature of the property, the owner thereof has the right to properly use it (as a durable, mean or factor, or whatever), or at the very least exclusively keep it.
In economics and political economy, there are three broad forms of property: private property, public property, and collective property (also called cooperative property).[4]
Property that jointly belongs to more than one party may be possessed or controlled thereby in very similar or very distinct ways, whether simply or complexly, whether equally or unequally. However, there is an expectation that each party's will (rather discretion) with regard to the property be clearly defined and unconditional,[citation needed] so as to distinguish ownership and easement from rent. The parties might expect their wills to be unanimous, or alternately every given one of them, when no opportunity for or possibility of dispute with any other of them exists, may expect his, her, its or their own will to be sufficient and absolute.
The Restatement (First) of Property defines property as anything, tangible or intangible whereby a legal relationship between persons and the state enforces a possessory interest or legal title in that thing. This mediating relationship between individual, property and state is called a property regime.[5]
In sociology and anthropology, property is often defined as a relationship between two or more individuals and an object, in which at least one of these individuals holds a bundle of rights over the object. The distinction between 'collective property' and 'private property' is regarded as a confusion since different individuals often hold differing rights over a single object.[6][7]
Important widely recognized types of property include real property (the combination of land and any improvements to or on the land), personal property (physical possessions belonging to a person), private property (property owned by legal persons, business entities or individual natural persons), public property (state owned or publicly owned and available possessions) and intellectual property (exclusive rights over artistic creations, inventions, etc.), although the last is not always as widely recognized or enforced.[8] An article of property may have physical and incorporeal parts. A title, or a right of ownership, establishes the relation between the property and other persons, assuring the owner the right to dispose of the property as the owner sees fit.[citation needed]
- 1Overview
- 2Related concepts
- 3Issues in property theory
- 5Property in philosophy
- 5.2Medieval philosophy
- 5.3Modern philosophy
Overview[edit]
Often property is defined by the code of the local sovereignty, and protected wholly or more usually partially by such entity, the owner being responsible for any remainder of protection. The standards of proof concerning proofs of ownerships are also addressed by the code of the local sovereignty, and such entity plays a role accordingly, typically somewhat managerial. Some philosophers[who?] assert that property rights arise from social convention, while others find justifications for them in morality or in natural law.
Various scholarly disciplines (such as law, economics, anthropology or sociology) may treat the concept more systematically, but definitions vary, most particularly when involving contracts. Positive law defines such rights, and the judiciary can adjudicate and enforce property rights.
According to Adam Smith, the expectation of profit from 'improving one's stock of capital' rests on private property rights.[9]Capitalism has as a central assumption that property rights encourage their holders to develop the property, generate wealth, and efficiently allocate resources based on the operation of markets. From this has evolved the modern conception of property as a right enforced by positive law, in the expectation that this will produce more wealth and better standards of living. However, Smith also expressed a very critical view on the effects of property laws on inequality:
- 'Wherever there is great property, there is great inequality … Civil government, so far as it is instituted for the security of property, is in reality instituted for the defence of the rich against the poor, or of those who have some property against those who have none at all.'[10] (Adam Smith, Wealth of Nations)
In his text The Common Law, Oliver Wendell Holmes describes property as having two fundamental aspects. The first, possession, can be defined as control over a resource based on the practical inability of another to contradict the ends of the possessor. The second, title, is the expectation that others will recognize rights to control resource, even when it is not in possession. He elaborates the differences between these two concepts, and proposes a history of how they came to be attached to persons, as opposed to families or to entities such as the church.
- Classical liberalism subscribes to the labor theory of property. They hold that individuals each own their own life, it follows that one must own the products of that life, and that those products can be traded in free exchange with others.
- 'Every man has a property in his own person. This nobody has a right to, but himself.' (John Locke, Second Treatise on Civil Government)
- 'The reason why men enter into society is the preservation of their property.' (John Locke, Second Treatise on Civil Government)
- 'Life, liberty, and property do not exist because men have made laws. On the contrary, it was the fact that life, liberty, and property existed beforehand that caused men to make laws in the first place.' (Frédéric Bastiat, The Law)
- Conservatism subscribes to the concept that freedom and property are closely linked. That the more widespread the possession of private property, the more stable and productive is a state or nation. Economic leveling of property, conservatives maintain, especially of the forced kind, is not economic progress.
- 'Separate property from private possession, and Leviathan becomes master of all.. Upon the foundation of private property, great civilizations are built.. The conservative acknowledges that the possession of property fixes certain duties upon the possessor; he accepts those moral and legal obligations cheerfully.' (Russell Kirk, The Politics of Prudence)
- Socialism's fundamental principles center on a critique of this concept, stating (among other things) that the cost of defending property exceeds the returns from private property ownership, and that, even when property rights encourage their holders to develop their property or generate wealth, they do so only for their own benefit, which may not coincide with benefit to other people or to society at large.
- Libertarian socialism generally accepts property rights, but with a short abandonment period. In other words, a person must make (more-or-less) continuous use of the item or else lose ownership rights. This is usually referred to as 'possession property' or 'usufruct'. Thus, in this usufruct system, absentee ownership is illegitimate and workers own the machines or other equipment that they work with.
- Communism argues that only collective ownership of the means of production through a polity (though not necessarily a state) will assure the minimization of unequal or unjust outcomes and the maximization of benefits, and that therefore humans should abolish private ownership of capital (as opposed to property).
Both communism and some kinds of socialism have also upheld the notion that private ownership of capital is inherently illegitimate. This argument centers mainly on the idea that private ownership of capital always benefits one class over another, giving rise to domination through the use of this privately owned capital. Communists do not oppose personal property that is 'hard-won, self-acquired, self-earned' (as the Communist Manifesto puts it) by members of the proletariat. Both socialism and communism distinguish carefully between private ownership of capital (land, factories, resources, etc.) and private property (homes, material objects and so forth).
Types of property[edit]
Most legal systems distinguish between different types of property, especially between land (immovable property, estate in land, real estate, real property) and all other forms of property—goods and chattels, movable property or personal property, including the value of legal tender if not the legal tender itself, as the manufacturer rather than the possessor might be the owner. They often distinguish tangible and intangible property. One categorization scheme specifies three species of property: land, improvements (immovable man-made things), and personal property (movable man-made things).[citation needed]
In common law, real property (immovable property) is the combination of interests in land and improvements thereto, and personal property is interest in movable property. Real property rights are rights relating to the land. These rights include ownership and usage. Owners can grant rights to persons and entities in the form of leases, licenses and easements.
Throughout the last centuries of the second millennium, with the development of more complex theories of property, the concept of personal property had become divided[by whom?] into tangible property (such as cars and clothing) and intangible property (such as financial instruments, including stocks and bonds; intellectual property, including patents, copyrights and trademarks; digital files; communication channels; and certain forms of identifier, including Internet domain names, some forms of network address, some forms of handle and again trademarks).
Treatment of intangible property is such that an article of property is, by law or otherwise by traditional conceptualization, subject to expiration even when inheritable, which is a key distinction from tangible property. Upon expiration, the property, if of the intellectual category, becomes a part of public domain, to be used by but not owned by anybody, and possibly used by more than one party simultaneously due the inapplicability of scarcity to intellectual property. Whereas things such as communications channels and pairs of electromagnetic spectrum band and signal transmission power can only be used by a single party at a time, or a single party in a divisible context, if owned or used at all. Thus far or usually those are not considered property, or at least not private property, even though the party bearing right of exclusive use may transfer that right to another.
Related concepts[edit]
Of the following, only sale and at-will sharing involve no encumbrance.
General meaning or description | Actor | Complementary notion | Complementary actor | ||
---|---|---|---|---|---|
Sale | Giving of property or ownership, but in exchange for money (units of some form of currency). | Seller | Buying | Buyer | |
Sharing | Sharing | Allowing use of property, whether exclusive or as a joint operation. | Host | Accommodation | Guest |
Tenancy | Tenant | ||||
Rent | Allowing limited and temporary but potentially renewable, exclusive use of property, but in exchange for compensation. | Renter | |||
Lease | Leasee | ||||
Licensure | Licensor | ||||
Incorporeal division | Incorporeal division | Better known as nonpossessory interest or variation of the same notion, of which an instance may be given to another party, which is itself an incorporeal form of property. The particular interest may easily be destroyed once it and the property are owned by the same party. | N/A | ||
Share | Aspect of property whereby ownership or equity of a particular portion of all property (stock) ever to be produced from it may be given to another party, which is itself an incorporeal form of property. The share may easily be destroyed once it and the property are owned by the same party. | ||||
Easement | Aspect of property whereby right of particular use of it may be given to another party, which is itself an incorporeal form of property. The easement or use-right may easily be destroyed once it and the property are owned by the same party. | ||||
Lien | Lien | Condition whereby unencumbered ownership of property is contingent upon completion of obligation; the property being collateral and associated with security interest in such an arrangement. | Lienor | Lieneeship | Lienee |
Mortgage | Condition whereby while possession of property is achieved or retained, possession of it is contingent upon performance of obligation to somebody indebted to, and unencumbered ownership of it is contingent upon completion of obligation. The performance of obligation usually implies division of the principal into installments. | Mortgagor | Mortgage-brokering | Mortgage-broker | |
Pawn | Condition whereby while encumbered ownership of property is achieved or retained, encumbered ownership of it is contingent upon performance of obligation to somebody indebted to, and possession and unencumbered ownership of it is contingent upon completion of obligation. | Pledge | Pawnbrokering | Pawnbroker | |
Collision (Conflict) | Inability for property to be properly used or occupied due to scarcity or contradiction, the effective impossibility of sharing; possibly leading to eviction or the contrary, if resolution is achieved rather than a stagnant condition; not necessarily involving or implying conscious dispute. | N/A | |||
Security (Ward) | Degree of resistance to or protection from harm, use or taking; the property and any mechanisms of protection of it being ward. (Alternately, in finance, the word as a countable noun refers to proof of ownership of investment instruments, or as an uncountable noun to collateral.) In general, there may be an involvement of obscurities, camouflage, barriers, armor, locks, alarms, booby traps, homing beacons, automated recorders, decoys, weaponry or sentinels.
| Securer | Protecteeship | Protectee | |
Warden | Ward |
Violation[edit]
General meaning or description, the act occurring in a way not beholden to the wishes of the owner | Committer | |
---|---|---|
Trespassing | Use of physical and usually but not necessarily only immovable property or occupation of it. | Trespasser |
Vandalism | Alteration, damage or destruction of physical property or to the appearance of it. | Vandal |
Infringement | (Incorporeal analogy to trespassing.) Alteration or duplication of an instance of intellectual property, and publication of the respectively alternate or duplicate; the instance being the information in a medium or a device for which a design plan predates and is the basis of fabrication. | Infringer |
Violation | Violator | |
Theft | Taking of property in a way that excludes the owner from it, or active alteration of the ownership of property. | Thief |
Piracy | The cognisant or incognisant reproduction and distribution of intellectual property as well as the possession of intellectual property that saw publication of its duplicates in the aforementioned process. | |
Infringement with the effect of lost profits for the owner or infringement involving profit or personal gain. | ||
Plagiarism | Publication of a work, whether it is intellectual property (perhaps copyrighted) or not, whether it is in public domain or not, without credit being afforded to the creator, as though the work is original in publication. | Plagiarist |
Miscellaneous action[edit]
General meaning or description | Committer | |
---|---|---|
Squatting | Occupation of property that either is unused and unkept or was abandoned, whether the property still has an owner or not. (If the property is owned and not abandoned, then the squatting is trespassing, if any usage not beholden to the wishes of the owner is done in the process.) | Squatter |
Reverse engineering | Discovery of how a device works, whether it is an instance of intellectual property (perhaps patented) or not, whether it is in public domain or not, and of how to alter or duplicate it, without access to or knowledge of the corresponding design plan. | Reverse engineer |
Ghostwriting | Creation of a textual work, whereby in publication, another party is explicitly allowed to be credited as creator. | Ghostwriter |
Issues in property theory[edit]
What can be property?[edit]
The two major justifications given for original property, or the homestead principle, are effort and scarcity. John Locke emphasized effort, 'mixing your labor'[11] with an object, or clearing and cultivating virgin land. Benjamin Tucker preferred to look at the telos of property, i.e. What is the purpose of property? His answer: to solve the scarcity problem. Only when items are relatively scarce with respect to people's desires do they become property.[12] For example, hunter-gatherers did not consider land to be property, since there was no shortage of land. Agrarian societies later made arable land property, as it was scarce. For something to be economically scarce it must necessarily have the exclusivity property—that use by one person excludes others from using it. These two justifications lead to different conclusions on what can be property. Intellectual property—incorporeal things like ideas, plans, orderings and arrangements (musical compositions, novels, computer programs)—are generally considered valid property to those who support an effort justification, but invalid to those who support a scarcity justification, since the things don't have the exclusivity property (however, those who support a scarcity justification may still support other 'intellectual property' laws such as Copyright, as long as these are a subject of contract instead of government arbitration). Thus even ardent propertarians may disagree about IP.[13] By either standard, one's body is one's property.
From some anarchist points of view, the validity of property depends on whether the 'property right' requires enforcement by the state. Different forms of 'property' require different amounts of enforcement: intellectual property requires a great deal of state intervention to enforce, ownership of distant physical property requires quite a lot, ownership of carried objects requires very little, while ownership of one's own body requires absolutely no state intervention. Some anarchists don't believe in property at all.
Many things have existed that did not have an owner, sometimes called the commons. The term 'commons,' however, is also often used to mean something quite different: 'general collective ownership'—i.e. common ownership. Also, the same term is sometimes used by statists to mean government-owned property that the general public is allowed to access (public property). Law in all societies has tended to develop towards reducing the number of things not having clear owners. Supporters of property rights argue that this enables better protection of scarce resources, due to the tragedy of the commons, while critics argue that it leads to the 'exploitation' of those resources for personal gain and that it hinders taking advantage of potential network effects. These arguments have differing validity for different types of 'property'—things that are not scarce are, for instance, not subject to the tragedy of the commons. Some apparent critics advocate general collective ownership rather than ownerlessness.
Things that do not have owners include: ideas (except for intellectual property), seawater (which is, however, protected by anti-pollution laws), parts of the seafloor (see the United Nations Convention on the Law of the Sea for restrictions), gases in Earth's atmosphere, animals in the wild (although in most nations, animals are tied to the land. In the United States and Canada wildlife are generally defined in statute as property of the state. This public ownership of wildlife is referred to as the North American Model of Wildlife Conservation and is based on The Public Trust Doctrine.[14]), celestial bodies and outer space, and land in Antarctica.
The nature of children under the age of majority is another contested issue here. In ancient societies children were generally considered the property of their parents. Children in most modern societies theoretically own their own bodies but are not considered competent to exercise their rights, and their parents or guardians are given most of the actual rights of control over them.
Questions regarding the nature of ownership of the body also come up in the issue of abortion, drugs and euthanasia.
In many ancient legal systems (e.g. early Roman law), religious sites (e.g. temples) were considered property of the God or gods they were devoted to. However, religious pluralism makes it more convenient to have religious sites owned by the religious body that runs them.
Intellectual property and air (airspace, no-fly zone, pollution laws, which can include tradable emissions rights) can be property in some senses of the word.
Ownership of land can be held separately from the ownership of rights over that land, including sporting rights,[15]mineral rights, development rights, air rights, and such other rights as may be worth segregating from simple land ownership.
Who can be an owner?[edit]
Ownership laws may vary widely among countries depending on the nature of the property of interest (e.g. firearms, real property, personal property, animals). Persons can own property directly. In most societies legal entities, such as corporations, trusts and nations (or governments) own property.
In many countries women have limited access to property following restrictive inheritance and family laws, under which only men have actual or formal rights to own property.
In the Inca empire, the dead emperors, who were considered gods, still controlled property after death.[16]
Whether and to what extent the state may interfere with property[edit]
In 17th-century England, the legal directive that nobody may enter a home, which in the 17th-century would typically have been male owned, unless by the owners invitation or consent, was established as common law in Sir Edward Coke’s Institutes of the Lawes of England. 'For a man's house is his castle, et domus sua cuique est tutissimum refugium [and each man's home is his safest refuge].' It is the origin of the famous dictum, “an Englishman’s home is his castle”.[17] The ruling enshrined into law what several English writers had espoused in the 16th-century.[17] Unlike the rest of Europe the British had a proclivity towards owning their own homes.[17] British Prime Minister William Pitt, 1st Earl of Chatham defined the meaning of castle in 1763, 'The poorest man may in his cottage bid defiance to all the forces of the crown. It may be frail – its roof may shake – the wind may blow through it – the storm may enter – the rain may enter – but the King of England cannot enter.'[17]
A principle exported to the United States, under U.S. law the principal limitations on whether and the extent to which the State may interfere with property rights are set by the Constitution. The 'Takings' clause requires that the government (whether state or federal—for the 14th Amendment's due process clause imposes the 5th Amendment's takings clause on state governments) may take private property only for a public purpose, after exercising due process of law, and upon making 'just compensation.' If an interest is not deemed a 'property' right or the conduct is merely an intentional tort, these limitations do not apply and the doctrine of sovereign immunity precludes relief.[18] Moreover, if the interference does not almost completely make the property valueless, the interference will not be deemed a taking but instead a mere regulation of use.[19] On the other hand, some governmental regulations of property use have been deemed so severe that they have been considered 'regulatory takings.'[20] Moreover, conduct sometimes deemed only a nuisance or other tort has been held a taking of property where the conduct was sufficiently persistent and severe.[21]
Theories[edit]
There exist many theories of property. One is the relatively rare first possession theory of property, where ownership of something is seen as justified simply by someone seizing something before someone else does.[22] Perhaps one of the most popular is the natural rights definition of property rights as advanced by John Locke. Locke advanced the theory that God granted dominion over nature to man through Adam in the book of Genesis. Therefore, he theorized that when one mixes one's labor with nature, one gains a relationship with that part of nature with which the labor is mixed, subject to the limitation that there should be 'enough, and as good, left in common for others.' (see Lockean proviso)[23]
From the RERUM NOVARUM, Pope Leo XIII wrote 'It is surely undeniable that, when a man engages in remunerative labor, the impelling reason and motive of his work is to obtain property, and thereafter to hold it as his very own.'
Anthropology studies the diverse systems of ownership, rights of use and transfer, and possession[24] under the term 'theories of property.' Western legal theory is based, as mentioned, on the owner of property being a legal person. However, not all property systems are founded on this basis.
In every culture studied ownership and possession are the subject of custom and regulation, and 'law' where the term can meaningfully be applied. Many tribal cultures balance individual ownership with the laws of collective groups: tribes, families, associations and nations. For example, the 1839 Cherokee Constitution frames the issue in these terms:
Sec. 2. The lands of the Cherokee Nation shall remain common property; but the improvements made thereon, and in the possession of the citizens respectively who made, or may rightfully be in possession of them: Provided, that the citizens of the Nation possessing exclusive and indefeasible right to their improvements, as expressed in this article, shall possess no right or power to dispose of their improvements, in any manner whatever, to the United States, individual States, or to individual citizens thereof; and that, whenever any citizen shall remove with his effects out of the limits of this Nation, and become a citizen of any other government, all his rights and privileges as a citizen of this Nation shall cease: Provided, nevertheless, That the National Council shall have power to re-admit, by law, to all the rights of citizenship, any such person or persons who may, at any time, desire to return to the Nation, on memorializing the National Council for such readmission.
Communal property systems describe ownership as belonging to the entire social and political unit. Such arrangements can under certain conditions erode open access resources. This development has been critiqued by the tragedy of the commons.
Fuji 35 F2 Manual Focus
Corporate systems describe ownership as being attached to an identifiable group with an identifiable responsible individual. The Roman property law was based on such a corporate system. In a well-known paper that contributed to the creation of the field of law and economics in the late 1960s, the American scholar Harold Demsetz described how the concept of property rights makes social interactions easier:
In the world of Robinson Crusoe property rights play no role. Property rights are an instrument of society and derive their significance from the fact that they help a man form those expectations which he can reasonably hold in his dealings with others. These expectations find expression in the laws, customs, and mores of a society. An owner of property rights possesses the consent of fellowmen to allow him to act in particular ways. An owner expects the community to prevent others from interfering with his actions, provided that these actions are not prohibited in the specifications of his rights.
Different societies may have different theories of property for differing types of ownership. Pauline Peters argued that property systems are not isolable from the social fabric, and notions of property may not be stated as such, but instead may be framed in negative terms: for example the taboo system among Polynesian peoples.
Property in philosophy[edit]
In medieval and RenaissanceEurope the term 'property' essentially referred to land. After much rethinking, land has come to be regarded as only a special case of the property genus. This rethinking was inspired by at least three broad features of early modern Europe: the surge of commerce, the breakdown of efforts to prohibit interest (then called 'usury'), and the development of centralized national monarchies.
Ancient philosophy[edit]
Urukagina, the king of the Sumerian city-state Lagash, established the first laws that forbade compelling the sale of property.[26]
The Ten Commandments shown in Exodus 20:2–17 and Deuteronomy 5:6–21 stated that the Israelites were not to steal, but the connection between Bronze Age concepts of theft and modern concepts of property is suspect.
Aristotle, in Politics, advocates 'private property.' [27][citation needed] He argues that self-interest leads to neglect of the commons. '[T]hat which is common to the greatest number has the least care bestowed upon it. Every one thinks chiefly of his own, hardly at all of the common interest; and only when he is himself concerned as an individual.'[citation needed][28]
In addition he says that when property is common, there are natural problems that arise due to differences in labor: 'If they do not share equally enjoyments and toils, those who labor much and get little will necessarily complain of those who labor little and receive or consume much. But indeed there is always a difficulty in men living together and having all human relations in common, but especially in their having common property.' (Politics, 1261b34)
Cicero held that there is no private property under natural law but only under human law.[29]Seneca viewed property as only becoming necessary when men become avarice.[30]St. Ambrose later adopted this view and St. Augustine even derided heretics for complaining the Emperor could not confiscate property they had labored for.[31]
Medieval philosophy[edit]
Thomas Aquinas (13th century)[edit]
The canon law Decretum Gratiani maintained that mere human law creates property, repeating the phrases used by St. Augustine.[32]St. Thomas Aquinas agreed with regard to the private consumption of property but modified patristic theory in finding that the private possession of property is necessary.[33] Thomas Aquinas concludes that, given certain detailed provisions,[34]
- it is natural for man to possess external things
- it is lawful for a man to possess a thing as his own
- the essence of theft consists in taking another's thing secretly
- theft and robbery are sins of different species, and robbery is a more grievous sin than theft
- theft is a sin; it is also a mortal sin
- it is, however, lawful to steal through stress of need: 'in cases of need all things are common property.'
Modern philosophy[edit]
Thomas Hobbes (17th century)[edit]
The principal writings of Thomas Hobbes appeared between 1640 and 1651—during and immediately following the war between forces loyal to King Charles I and those loyal to Parliament. In his own words, Hobbes' reflection began with the idea of 'giving to every man his own,' a phrase he drew from the writings of Cicero. But he wondered: How can anybody call anything his own? He concluded: My own can only truly be mine if there is one unambiguously strongest power in the realm, and that power treats it as mine, protecting its status as such.[35]
James Harrington (17th century)[edit]
A contemporary of Hobbes, James Harrington, reacted to the same tumult in a different way: he considered property natural but not inevitable. The author of Oceana, he may have been the first political theorist to postulate that political power is a consequence, not the cause, of the distribution of property. He said that the worst possible situation is one in which the commoners have half a nation's property, with crown and nobility holding the other half—a circumstance fraught with instability and violence. A much better situation (a stable republic) will exist once the commoners own most property, he suggested.
In later years, the ranks of Harrington's admirers included American revolutionary and founder John Adams.
Robert Filmer (17th century)[edit]
Another member of the Hobbes/Harrington generation, Sir Robert Filmer, reached conclusions much like Hobbes', but through Biblicalexegesis. Filmer said that the institution of kingship is analogous to that of fatherhood, that subjects are but children, whether obedient or unruly, and that property rights are akin to the household goods that a father may dole out among his children—his to take back and dispose of according to his pleasure.
John Locke (17th century)[edit]
In the following generation, John Locke sought to answer Filmer, creating a rationale for a balanced constitution in which the monarch had a part to play, but not an overwhelming part. Since Filmer's views essentially require that the Stuart family be uniquely descended from the patriarchs of the Bible, and since even in the late 17th century that was a difficult view to uphold, Locke attacked Filmer's views in his First Treatise on Government, freeing him to set out his own views in the Second Treatise on Civil Government. Therein, Locke imagined a pre-social world, each of the unhappy residents of which are willing to create a social contract because otherwise 'the enjoyment of the property he has in this state is very unsafe, very unsecure,' and therefore the 'great and chief end, therefore, of men's uniting into commonwealths, and putting themselves under government, is the preservation of their property.'[36] They would, he allowed, create a monarchy, but its task would be to execute the will of an elected legislature. 'To this end' (to achieve the previously specified goal), he wrote, 'it is that men give up all their natural power to the society they enter into, and the community put the legislative power into such hands as they think fit, with this trust, that they shall be governed by declared laws, or else their peace, quiet, and property will still be at the same uncertainty as it was in the state of nature.'[37]
Even when it keeps to proper legislative form, though, Locke held that there are limits to what a government established by such a contract might rightly do.
'It cannot be supposed that [the hypothetical contractors] they should intend, had they a power so to do, to give any one or more an absolute arbitrary power over their persons and estates, and put a force into the magistrate's hand to execute his unlimited will arbitrarily upon them; this were to put themselves into a worse condition than the state of nature, wherein they had a liberty to defend their right against the injuries of others, and were upon equal terms of force to maintain it, whether invaded by a single man or many in combination. Whereas by supposing they have given up themselves to the absolute arbitrary power and will of a legislator, they have disarmed themselves, and armed him to make a prey of them when he pleases..'[38]
Note that both 'persons and estates' are to be protected from the arbitrary power of any magistrate, inclusive of the 'power and will of a legislator.' In Lockean terms, depredations against an estate are just as plausible a justification for resistance and revolution as are those against persons. In neither case are subjects required to allow themselves to become prey.
To explain the ownership of property Locke advanced a labor theory of property.
David Hume (18th century)[edit]
In contrast to the figures discussed in this section thus far David Hume lived a relatively quiet life that had settled down to a relatively stable social and political structure. He lived the life of a solitary writer until 1763 when, at 52 years of age, he went off to Paris to work at the British embassy.
In contrast, one might think, to his polemical works on religion and his empiricism-driven skepticalepistemology, Hume's views on law and property were quite conservative.
He did not believe in hypothetical contracts, or in the love of mankind in general, and sought to ground politics upon actual human beings as one knows them. 'In general,' he wrote, 'it may be affirmed that there is no such passion in human mind, as the love of mankind, merely as such, independent of personal qualities, or services, or of relation to ourselves.' Existing customs should not lightly be disregarded, because they have come to be what they are as a result of human nature. With this endorsement of custom comes an endorsement of existing governments, because he conceived of the two as complementary: 'A regard for liberty, though a laudable passion, ought commonly to be subordinate to a reverence for established government.'
Therefore, Hume's view was that there are property rights because of and to the extent that the existing law, supported by social customs, secure them.[39] He offered some practical home-spun advice on the general subject, though, as when he referred to avarice as 'the spur of industry,' and expressed concern about excessive levels of taxation, which 'destroy industry, by engendering despair.'
Adam Smith[edit]
Civil government, so far as it is instituted for the security of property, is, in reality, instituted for the defense of the rich against the poor, or of those who have property against those who have none at all.
'The property which every man has in his own labour, as it is the original foundation of all other property, so it is the most sacred and inviolable. The patrimony of a poor man lies in the strength and dexterity of his hands; and to hinder him from employing this strength and dexterity in what manner he thinks proper without injury to his neighbour, is a plain violation of this most sacred property. It is a manifest encroachment upon the just liberty both of the workman, and of those who might be disposed to employ him. As it hinders the one from working at what he thinks proper, so it hinders the others from employing whom they think proper. To judge whether he is fit to be employed, may surely be trusted to the discretion of the employers whose interest it so much concerns. The affected anxiety of the law-giver lest they should employ an improper person, is evidently as impertinent as it is oppressive.'— (Source: Adam Smith, The Wealth of Nations, 1776, Book I, Chapter X, Part II.)
By the mid 19th century, the industrial revolution had transformed England and the United States, and had begun in France. The established conception of what constitutes property expanded beyond land to encompass scarce goods in general. In France, the revolution of the 1790s had led to large-scale confiscation of land formerly owned by church and king. The restoration of the monarchy led to claims by those dispossessed to have their former lands returned.
Karl Marx[edit]
Section VIII, 'Primitive Accumulation' of Capital involves a critique of Liberal Theories of property rights. Marx notes that under Feudal Law, peasants were legally as entitled to their land as the aristocracy was to its manors. Marx cites several historical events in which large numbers of the peasantry were removed from their lands, which were then seized by the aristocracy. This seized land was then used for commercial ventures (sheep herding). Marx sees this 'Primitive Accumulation' as integral to the creation of English Capitalism. This event created a large un-landed class which had to work for wages in order to survive. Marx asserts that Liberal theories of property are 'idyllic' fairy tales that hide a violent historical process.
Charles Comte: legitimate origin of property[edit]
Charles Comte, in Traité de la propriété (1834), attempted to justify the legitimacy of private property in response to the Bourbon Restoration. According to David Hart, Comte had three main points: 'firstly, that interference by the state over the centuries in property ownership has had dire consequences for justice as well as for economic productivity; secondly, that property is legitimate when it emerges in such a way as not to harm anyone; and thirdly, that historically some, but by no means all, property which has evolved has done so legitimately, with the implication that the present distribution of property is a complex mixture of legitimately and illegitimately held titles.'[41]
Comte, as Proudhon later did, rejected Roman legal tradition with its toleration of slavery. He posited a communal 'national' property consisting of non-scarce goods, such as land in ancient hunter-gatherer societies. Since agriculture was so much more efficient than hunting and gathering, private property appropriated by someone for farming left remaining hunter-gatherers with more land per person, and hence did not harm them. Thus this type of land appropriation did not violate the Lockean proviso – there was 'still enough, and as good left.' Comte's analysis would be used by later theorists in response to the socialist critique on property.
Pierre-Joseph Proudhon: property is theft[edit]
In his 1840 treatise What is Property?, Pierre Proudhon answers with 'Property is theft!' In natural resources, he sees two types of property, de jure property (legal title) and de facto property (physical possession), and argues that the former is illegitimate. Proudhon's conclusion is that 'property, to be just and possible, must necessarily have equality for its condition.'
His analysis of the product of labor upon natural resources as property (usufruct) is more nuanced. He asserts that land itself cannot be property, yet it should be held by individual possessors as stewards of mankind with the product of labor being the property of the producer. Proudhon reasoned that any wealth gained without labor was stolen from those who labored to create that wealth. Even a voluntary contract to surrender the product of labor to an employer was theft, according to Proudhon, since the controller of natural resources had no moral right to charge others for the use of that which he did not labor to create and therefore did not own.
Proudhon's theory of property greatly influenced the budding socialist movement, inspiring anarchist theorists such as Mikhail Bakunin who modified Proudhon's ideas, as well as antagonizing theorists like Karl Marx.
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Frédéric Bastiat: property is value[edit]
Frédéric Bastiat's main treatise on property can be found in chapter 8 of his book Economic Harmonies (1850).[42] In a radical departure from traditional property theory, he defines property not as a physical object, but rather as a relationship between people with respect to an object. Thus, saying one owns a glass of water is merely verbal shorthand for I may justly gift or trade this water to another person. In essence, what one owns is not the object but the value of the object. By 'value,' Bastiat apparently means market value; he emphasizes that this is quite different from utility. 'In our relations with one another, we are not owners of the utility of things, but of their value, and value is the appraisal made of reciprocal services.'
Bastiat theorized that, as a result of technological progress and the division of labor, the stock of communal wealth increases over time; that the hours of work an unskilled laborer expends to buy e.g. 100 liters of wheat decreases over time, thus amounting to 'gratis' satisfaction.[43] Thus, private property continually destroys itself, becoming transformed into communal wealth. The increasing proportion of communal wealth to private property results in a tendency toward equality of mankind. 'Since the human race started from the point of greatest poverty, that is, from the point where there were the most obstacles to be overcome, it is clear that all that has been gained from one era to the next has been due to the spirit of property.'
This transformation of private property into the communal domain, Bastiat points out, does not imply that private property will ever totally disappear. This is because man, as he progresses, continually invents new and more sophisticated needs and desires.
Andrew J. Galambos: a precise definition of property[edit]
Andrew J. Galambos (1924–1997) was an astrophysicist and philosopher who innovated a social structure that seeks to maximize human peace and freedom. Galambos’ concept of property was basic to his philosophy. He defined property as a man's life and all non-procreative derivatives of his life. (Because the English language is deficient in omitting the feminine form “man” when referring to humankind, it is implicit and obligatory that the feminine is included in the term “man”.)
Galambos taught that property is essential to a non-coercive social structure. That is why he defined freedom as follows: “Freedom is the societal condition that exists when every individual has full (100%) control over his own property.”[44] Galambos defines property as having the following elements:
- Primordial property, which is an individual's life
- Primary property, which includes ideas, thoughts, and actions
- Secondary property, which includes all tangible and intangible possessions which are derivatives of the individual's primary property.
Property includes all non-procreative derivatives of an individual's life; this means children are not the property of their parents.[45] and 'primary property' (a person's own ideas).[46]
Galambos emphasized repeatedly that true government exists to protect property and that the state attacks property.For example, the state requires payment for its services in the form of taxes whether or not people desire such services. Since an individual's money is his property, the confiscation of money in the form of taxes is an attack on property. Military conscription is likewise an attack on a person's primordial property.
Contemporary views[edit]
Contemporary political thinkers who believe that natural persons enjoy rights to own property and to enter into contracts espouse two views about John Locke. On the one hand, some admire Locke, such as William H. Hutt (1956), who praised Locke for laying down the 'quintessence of individualism'. On the other hand, those such as Richard Pipes regard Locke's arguments as weak, and think that undue reliance thereon has weakened the cause of individualism in recent times. Pipes has written that Locke's work 'marked a regression because it rested on the concept of Natural Law' rather than upon Harrington's sociological framework.
Hernando de Soto has argued that an important characteristic of capitalist market economy is the functioning state protection of property rights in a formal property system which clearly records ownership and transactions. These property rights and the whole formal system of property make possible:
- Greater independence for individuals from local community arrangements to protect their assets
- Clear, provable, and protectable ownership
- The standardization and integration of property rules and property information in a country as a whole
- Increased trust arising from a greater certainty of punishment for cheating in economic transactions
- More formal and complex written statements of ownership that permit the easier assumption of shared risk and ownership in companies, and insurance against risk
- Greater availability of loans for new projects, since more things can serve as collateral for the loans
- Easier access to and more reliable information regarding such things as credit history and the worth of assets
- Increased fungibility, standardization and transferability of statements documenting the ownership of property, which paves the way for structures such as national markets for companies and the easy transportation of property through complex networks of individuals and other entities
- Greater protection of biodiversity due to minimizing of shifting agriculture practices
All of the above, according to de Soto, enhance economic growth.[47]
See also[edit]
Property-giving (legal)
- Tithe, Zakat (modern sense)
Property-taking (legal)
- Turf and twig (historical)
- Tithe, Zakat (historical sense)
Property-taking (illegal)
References[edit]
- ^'property definition', BusinessDictionary.com
- ^'property', American Heritage Dictionary
- ^'property', WordNet, retrieved 2010-06-19
- ^Gregory, Paul R.; Stuart, Robert C. (2003). Comparing Economic Systems in the Twenty-First Century. Boston: Houghton Mifflin. p. 27. ISBN0-618-26181-8.
There are three broad forms of property ownership-private, public, and collective (cooperative).
- ^Pellissery, Sony and Dey Biswas, Sattwick (2012) Emerging Property Regimes In India: What It Holds For the Future of Socio-Economic Rights? IRMA Working Paper 234
- ^Graeber, New York: Palgrave (2001) Toward an Anthropological Theory of Value: The False Coin of Our Own Dreams. ISBN978-0-312-24044-8 '.. one might argue that property is a social relation as well, reified in exactly the same way: when one buys a car one is not really purchasing the right to use it so much as the right to prevent others from using it-or, to be even more precise, one is purchasing their recognition that one has the right to do so. But since it is so diffuse a social relation- a contract, in effect, between the owner and everyone else in the entire world-it is easy to think of it as a thing..' (p. 9)
- ^Max Planck Institute for Social Anthropology, Property in Anthropology, 'Archived copy'. Archived from the original on 2015-01-16. Retrieved 2015-01-15.CS1 maint: Archived copy as title (link)
- ^Anti-copyright advocates and other critics of intellectual property dispute the concept of intellectual property.[1].
- ^Understanding the Global Economy, Howard Richards (p. 355). Peace Education Books. 2004. ISBN978-0-9748961-0-6.
- ^An inquiry into the nature and causes of the wealth of nations (p. 177). Hackett Publishing Company. 1993. ISBN0-87220-204-6. Retrieved 2011-12-15.
- ^'John Locke: Second Treatise of Civil Government: Chapter 5'. Retrieved 14 May 2015.
- ^'News – WendyMcElroy.com'. Archived from the original on 6 July 2008. Retrieved 14 May 2015.
- ^'Molinari Institute – Anti-Copyright Resources'. Retrieved 14 May 2015.
- ^'The North American Model of Wildlife Conservation and Public Trust Doctrine'. Archived from the original on 2012-01-19. Retrieved 2012-08-19.
- ^'Archived copy'(PDF). Archived from the original(PDF) on 2008-02-27. Retrieved 2007-12-31.CS1 maint: Archived copy as title (link)
- ^Mckay, John P. , 2004, 'A History of World Societes'. Boston: Houghton Mifflin Company
- ^ abcd'An Englishman's home is his castle'. Phrases.org.uk. Retrieved 6 December 2018.
- ^See, for example, United States v. Willow River Power Co. (not a property right because force of law not behind it); Schillinger v. United States, 155 U.S. 163 (1894) (patent infringement is tort, not taking of property); Zoltek Corp. v. United States, 442 F.3d 1345 (Fed. Cir. 2006).
- ^Penn Central Transportation Co. v. City of New York, 438 U.S. 104 (1978).
- ^See United States v. Riverside Bayview Homes, 474 U.S. 121 (1985).
- ^United States v. Causby, 328 U.S. 256 (1946).
- ^'Property'. Graham Oppy. The shorter Routledge encyclopedia of philosophy. Editor Edward Craig. Routledge, 2005, p. 858
- ^Locke, John (1690). 'The Second Treatise of Civil Government'. Retrieved 2010-06-26.
- ^Hann, Chris A new double movement? Anthropological perspectives on property in the age of neoliberalism Socio-Economic Review, Volume 5, Number 2, April 2007, pp. 287–318(32)
- ^Cited in Merrill & Smith (2017), pp. 238–39.
- ^Samuel Noah Kramer. From the Tablets of Sumer: Twenty-Five Firsts in Man's Recorded History. Indian Hills: The Falcon's Wing Press, 1956.
- ^'Property and Freedom'. www.nytimes.com. Retrieved 2018-01-10.
- ^This bears some similarities to the over-use argument of Garrett Hardin's 'Tragedy of the Commons'.
- ^Carlyle, A.J. (1913). Property: Its Duties and Rights. London: Macmillan. p. 121. Retrieved 4 April 2015. citing Cicero, De officiis, i. 7, 'Sunt autem privata nulla natura'.
- ^Carlyle, A.J. (1913). Property: Its Duties and Rights. London: Macmillan. p. 122. Retrieved 4 April 2015. citing Seneca, Epistles, xiv, 2.
- ^Carlyle, A.J. (1913). Property: Its Duties and Rights. London: Macmillan. p. 125. Retrieved 4 April 2015.
- ^Carlyle, A.J. (1913). Property: Its Duties and Rights. London: Macmillan. p. 127. Retrieved 4 April 2015. citing Decretum, D. viii. Part I.
- ^Carlyle, A.J. (1913). Property: Its Duties and Rights. London: Macmillan. p. 128. Retrieved 4 April 2015.
- ^'Summa Theologica: Theft and robbery (Secunda Secundae Partis, Q. 66)'. Retrieved 14 May 2015.
- ^'The Origin of Property'. Anti Essays. 27 May 2012, <http://www.antiessays.com/free-essays/226947.html>
- ^John Locke, The Second Treatise of Civil Government (1690), Chap. IX, §§ 123–124.
- ^John Locke, The Second Treatise of Civil Government (1690), Chap. XI, § 136.
- ^John Locke, The Second Treatise of Civil Government (1690), Chap. XI, § 137.
- ^This view is reflected in the opinion of the United States Supreme Court in United States v. Willow River Power Co..
- ^An Inquiry Into the Nature and Causes of the Wealth of Nations, by Adam Smith, Cooke & Hale, 1818, p. 167
- ^The Radical Liberalism of Charles Comte and Charles DunoyerArchived 2006-01-30 at the Wayback Machine
- ^Bastiat: Economic Harmonies.
- ^'Economic Harmonies (Boyers trans.) – Online Library of Liberty'. Retrieved 14 May 2015.
- ^Galambos, Andrew (1999). Sic Itur Ad Astra. San Diego, California: The Universal Scientific Publications Company, Inc. pp. 868–869. ISBN0-88078-004-5.
- ^Galambos, Andrew (1999). Sic Itur Ad Astra. San Diego, California: The Universal Scientific Publications Company, Inc. p. 23. ISBN0-88078-004-5.
- ^Galambos, Andrew (1999). Sic Itur Ad Astra. San Diego, California: The Universal Scientific Publications Company, Inc. pp. 39, 52, 84, 92–93, 153, 201, 326. ISBN0-88078-004-5.
- ^'Finance & Development, March 2001 – The Mystery of Capital'. Finance and Development – F&D. Retrieved 14 May 2015.
Bibliography[edit]
- Bastiat, Frédéric, 1850. Economic Harmonies. W. Hayden Boyers.
- Bastiat, Frédéric, 1850. 'The Law', tr. Dean Russell.
- Bethell, Tom, 1998. The Noblest Triumph: Property and Prosperity through the Ages. New York: St. Martin's Press.
- Blackstone, William, 1765–69. Commentaries on the Laws of England, 4 vols. Oxford Univ. Press. Especially Books the Second and Third.
- De Soto, Hernando, 1989. The Other Path. Harper & Row.
- De Soto, Hernando, and Francis Cheneval, 2006. Realizing Property Rights. Ruffer & Rub.
- Ellickson, Robert, 1993. ''Property in Land'(PDF). Archived from the original(PDF) on 2008-04-09.(6.40 MB)', Yale Law Journal 102: 1315–1400.
- Fruehwald, Edwin, 2010. A Biological Basis of Rights, 19 Southern California Interdisciplinary Law Journal 195.
- Mckay, John P., 2004, 'A History of World Societies'. Boston: Houghton Mifflin Company
- Palda, Filip (2011) Pareto's Republic and the New Science of Peace 2011 [2] chapters online. Published by Cooper-Wolfling. ISBN978-0-9877880-0-9
- Pipes, Richard, 1999. Property and Freedom. New York: Knopf Doubleday. ISBN978-0-375-40498-6
Fisher F2 Manual
External links[edit]
British Gas F2 Manual Dexterity Test
- Quotations related to Property at Wikiquote
- Concepts of Property, Hugh Breakey, Internet Encyclopedia of Philosophy
- 'Right to Private Property', Tibor Machan, Internet Encyclopedia of Philosophy
- Friedmann, Wolfgang (1974). 'Property'. In Wiener, Philip P. (ed.). Dictionary of the History of Ideas: Studies of Selected Pivotal Ideas. Volume 3 (University of Virginia, Electronic Text Center ed.). New York: Scribners. pp. 650–657.