Bates Method
Encyclopedia
The Bates method is an alternative therapy
aimed at improving eyesight
. Eye-care physician William Horatio Bates (1860–1931) attributed nearly all sight problems to habitual
strain of the eyes, and felt that glasses
were harmful and never necessary. Bates self-published a book as well as a magazine (and earlier collaborated with Bernarr MacFadden
on a correspondence course) detailing his approach to helping people relax such "strain", and thus, he claimed, improve their sight. His techniques centered around visualization and movement. He placed particular emphasis on imagining black
letters and marks, and the movement of such. He also felt that exposing the eyes to sunlight would help alleviate the "strain".
Despite continued anecdotal reports of successful results, including well-publicized support by Aldous Huxley
, Bates' techniques have not been shown objectively
to improve eyesight, and his main physiological proposition – that the eyeball changes shape to maintain focus
– has consistently been contradicted by observation. In 1952, optometry professor Elwin Marg wrote of Bates, “Most of his claims and almost all of his theories have been considered false by practically all visual scientists.” Marg concluded that the Bates method owed its popularity largely to "flashes of clear vision" experienced by many who followed it. Such occurrences have since been determined to most likely be a contact lens
-like effect of moisture on the eye.
Critics of the Bates method not only deny its efficacy, but go on to cite potential negative consequences for those who attempt to follow it, namely that they might overexpose their eyes to sunlight, put themselves and others at risk by not wearing their corrective lenses while driving, or neglect conventional eye care, possibly allowing serious conditions to develop.
is the process by which the eye increases optical power
to maintain focus
on the retina
while shifting its gaze to a closer point. The long-standing medical consensus is that this is accomplished by action of the ciliary muscle
, a muscle within the eye, which adjusts the curvature of the eye's crystalline lens
. This explanation is based in the observed effect of atropine
temporarily preventing accommodation when applied to the ciliary muscle, as well as images reflected on the crystalline lens becoming smaller as the eye shifts focus to a closer point, indicating a change in the lens' shape. Bates rejected this explanation, and in his 1920 book presented photographs which he said showed that the image remained the same size even as the eye shifted focus, concluding from this that the lens was not a factor in accommodation. However, optometrist Philip Pollack in a 1956 work characterized these photographs as "so blurred that it is impossible to tell whether one image is larger than the other", in contrast to later photographs
which clearly showed a change in the size of the reflected images, just as had been observed since the late nineteenth century.
Bates adhered to a different explanation of accommodation which had already been generally disregarded by the medical community of his time. This model had the muscles surrounding the eyeball
controlling its focus. In addition to their known function of turning the eye, Bates maintained, they also affect its shape, elongating the eyeball to focus at the near-point or shortening it to focus at a distance. Commenting on this hypothesis in an interview with WebMD
, ophthalmologist Richard E. Bensinger stated "When we put drops in the eye to dilate the pupil, they paralyze the focusing muscles. The evidence of the anatomical fallacy is that you can't focus, but your eye can move up and down, left and right. The notion that external muscles affect focusing is totally wrong." Science author John Grant
writes that many animals, such as fishes, accommodate by elongation of the eyeball, "it's just that humans aren't one of those animals."
Laboratory tests have shown that the eyeball is far too rigid to spontaneously change shape to a degree which would be necessary to accomplish what Bates described. Exceedingly small changes in axial length of the eyeball (18.6-19.2 micrometre
s) are caused by the action of the ciliary muscle during accommodation. However, these changes are far too small to account for the necessary changes in focus, producing changes of only -0.036 dioptre
s.
(the age-related blurring of near-point vision) as consequences of the eye's shape and other basic anatomy, which there is no evidence that any exercise can alter. Bates, however, believed that these conditions are caused by tension of the muscles surrounding the eyeball, which he believed prevents the eyeball from sufficiently changing shape (per his explanation of accommodation) when gaze is shifted nearer or farther. Bates characterized this supposed muscular tension as the consequence of a "mental strain" to see, the relief of which he claimed would instantly improve sight. He also linked disturbances in the circulation
of blood, which he said is "very largely influenced by thought", not only to refractive errors but also to double vision
, crossed-eye
, lazy eye
, and to more serious eye conditions such as cataract
s and glaucoma
. His therapies were based on these assumptions.
Bates felt that corrective lenses, which he characterized as "eye crutches", are an impediment to curing poor vision. In his view, "strain" would increase as the eyes adjust to the correction in front of them. He thus recommended that glasses
be discarded by anyone applying his method.
Bates suggested closing the eyes for minutes at a time to help bring about relaxation. He asserted that the relaxation could be deepened in most cases by "palming", or covering the closed eyes with the palms of the hands, without putting pressure on the eyeballs. If the covered eyes did not strain, he said, they would see "a field so black that it is impossible to remember, imagine, or see anything blacker", since light was excluded by the palms. However, he reported that some of his patients experienced "illusions of lights and colors" sometimes amounting to "kaleidoscopic appearances" as they "palmed", occurrences which he attributed to his ubiquitous "strain" and which he claimed disappeared when one truly relaxed. This phenomenon, however, was almost certainly caused by Eigengrau
or "dark light". In fact, even in conditions of perfect darkness, as inside a cave, neurons at every level of the visual system
produce random background activity that is interpreted by the brain as patterns of light and color.
s, as he felt relaxation was the key to clarity of imagination as well as of actual sight. He claimed that one's poise could be gauged by the visual memory of black; that the darker it appeared in the mind, and the smaller the area of black which could be imagined, the more relaxed one was at the moment. He recommended that patients think of the top letter from an eye chart
and then visualize progressively smaller black letters, and eventually a period or comma. But he emphasized his view that the clear visual memory of black "cannot be attained by any sort of effort", stating that "the memory is not the cause of the relaxation, but must be preceded by it", and cautioned against "concentrating" on black, as he regarded an attempt to "think of one thing only" as a strain.
While Bates preferred to have patients imagine something black, he also reported that some found objects of other colors easiest to visualize, and thus were benefited most by remembering those, because, he asserted, "the memory can never be perfect unless it is easy". Skeptics reason that the only benefit to eyesight gained from such techniques is itself imagined, and point out that familiar objects, including letters on an eye chart, can be recognized even when they appear less than clear.
Perhaps finding Bates' concepts of "shifting" and "swinging" too complicated, some proponents of vision improvement, such as Bernarr Macfadden
, suggested simply moving the eyes up and down, from side to side, and shifting one's gaze between a near-point and a far-point.
Bates believed that the eyes were benefited by exposure to sunlight. He stated that "persons with normal sight can look directly at the sun, or at the strongest artificial light, without injury or discomfort", and gave several examples of patients' vision purportedly improving after sungazing
—this is at variance with the well-known risk of eye damage
which can result from direct sunlight observation.
Bates cautioned that, just as one should not attempt to run a marathon without training, one should not immediately look directly at the sun, but he suggested that it could be worked up to. He acknowledged that looking at the sun could have ill effects, but characterized them as being "always temporary" and in fact the effects of strain in response to sunlight. He wrote that he had cured people who believed that the sun had caused them permanent eye damage. In his magazine, Bates later suggested exposing only the white part of the eyeball to direct sunlight, and only for seconds at a time, after allowing the sun to shine on closed eyelids for a longer period.
Eventually Bates concluded that the practice of sunning should only be done with closed eyelids. Posthumous publications of Bates' book omitted mention of the supposed benefits from direct sunlight shining on open eyes.
, and their supposed effectiveness in improving eyesight has not been substantiated by medical research. Several of Bates' techniques, including "sunning", "swinging", and "palming", were combined with healthy changes to diet and exercise in a 1983 randomized controlled trial
of myopic children in India. After 6 months, the experimental groups "did not show any statistically significant difference in refractive status", but the children in the treatment group "subjectively
... felt relieved of eye strain and other symptoms."
It has been argued, such as by philosopher Frank J. Leavitt, that the method which Bates described would be difficult to test
scientifically due to his emphasis on relaxation and visualization. Leavitt asked "How can we tell whether someone has relaxed or imagined something, or just thinks that he or she has imagined it?" In regards to the possibility of a placebo trial, Leavitt commented "I cannot conceive of how we could put someone in a situation where he thinks he has imagined something while we know that he has not."
In late 1940, Corbett and her assistant were charged with violations of the Medical Practice Act of California for treating eyes without a licence. At the trial, many of her students testified on her behalf, describing in detail how she had enabled them to discard their glasses. One witness testified that he had been almost blind from cataracts, but that, after working with Corbett, his vision had improved to such an extent that for the first time he could read for eight hours at a stretch without glasses. Corbett explained in court that she was practicing neither optometry
nor ophthalmology
and represented herself not as a doctor but only as an “instructor of eye training”. Describing her method she said "We turn vision on by teaching the eyes to shift. We want the sense of motion to relieve staring, to end the fixed look. We use light to relax the eyes and to accustom them to the sun."
The trial attracted widespread interest, as did the “not guilty” verdict. The case spurred a bill in the Californian State Legislature which would have then made such vision education illegal without an optometric or medical licence. After a lively campaign in the media, the bill was rejected.
Perhaps the most famous proponent of the Bates method was the British writer Aldous Huxley
. At the age of sixteen Huxley had an attack of keratitis
, which, after an 18-month period of near-blindness, left him with one eye just capable of light perception and the other with an unaided Snellen fraction of 10/200. This was mainly due to opacities in both cornea
s, complicated by hyperopia
and astigmatism
. He was able to read only if he wore thick glasses and dilated his better pupil with atropine
, to allow that eye to see around an opacity in the center of the cornea.
In 1939, at the age of 45 and with eyesight which continued to deteriorate, he happened to hear of the Bates method and sought the help of Margaret Corbett, who gave him regular lessons. Three years later he wrote The Art of Seeing
, in which he related: "Within a couple of months I was reading without spectacles and, what was better still, without strain and fatigue... At the present time, my vision, though very far from normal, is about twice as good as it used to be when I wore spectacles". Describing the process, Huxley wrote that "Vision is not won by making an effort to get it: it comes to those who have learned to put their minds and eyes into a state of alert passivity, of dynamic relaxation." He expressed indifference regarding the veracity of Bates' explanation of how the eye focuses, stating that "my concern is not with the anatomical mechanism of accommodation, but with the art of seeing".
His case generated wide publicity as well as scrutiny. Ophthalmologist Walter B. Lancaster, for example, suggested in 1944 that Huxley had "learned how to use what he has to better advantage" by training the "cerebral part of seeing", rather than actually improving the quality of the image on the retina
.
In 1952, ten years after writing The Art of Seeing, Huxley spoke at a Hollywood banquet, wearing no glasses and, according to Bennett Cerf
, apparently reading his paper from the lectern without difficulty. In Cerf's words:
In response to this, Huxley wrote "I often do use magnifying glasses where conditions of light are bad, and have never claimed to be able to read except under very good conditions." This underscored that he had not regained anything close to normal vision, and in fact never claimed that he had.
techniques. There are also many self-help
books and programs, which have not been subjected to randomized controlled trials, aimed at improving eyesight naturally. Purveyors of such approaches argue that they lack the funds to formally test them.
The heavily advertised "See Clearly Method
" (of which sales were halted by a court order in November 2006, in response to what were found to be dishonest marketing practices) included "palming" and "light therapy", both adapted from Bates. The creators of the program, however, emphasized that they did not endorse Bates' approach overall.
In his 1992 book The Bates Method, A Complete Guide to Improving Eyesight—Naturally, "Bates method teacher" Peter Mansfield was very critical of eye care professional
s for prescribing corrective lenses. He recommended most of Bates' techniques to improve vision, but omitted sungazing. The book included accounts of twelve instances of eyesight improving, but did not report any measurements of refractive error
.
Czech native John Slavicek claims to have created an "eye cure" that improves eyesight in three days, borrowing from ancient yogic eye exercises, visualizations from the Seth Material, and the Bates method. Although he has testimonials from his neighbor and others, several of his students indicate that he has greatly exaggerated their cases. Slavicek's self-published manual, Yoga for the Eyes, was rejected by an ophthalmologist who evaluated it, and evinced no interest from the World Health Organization
and St. Erik's Eye Foundation in Sweden as he had not conducted double-blind
tests.
, several potential explanations exist for the phenomena reported other than a genuine reversal of a refractive error
due to the techniques practiced:
is not due to any change in refractive error
. A 1982 study concluded that such occurrences are best explained as a contact lens
-like effect of moisture on the eye, based on increased tear action exhibited by 15 out of 17 subjects who experienced such improvement.
(AAO) published a review of various research regarding "visual training", which consisted of "eye exercises, muscle relaxation techniques, biofeedback, eye patches, or eye massages", "alone or in combinations". No evidence was found that such techniques could objectively
benefit eyesight, though some studies noted changes, both positive and negative, in the visual acuity
of nearsighted subjects as measured by a Snellen chart
. In some cases noted improvements were maintained at subsequent follow-ups. However, these results were not seen as actual reversals of nearsightedness, and were attributed instead to factors such as "improvements in interpreting blurred images, changes in mood or motivation, creation of an artificial contact lens by tear film changes, or a pinhole effect from miosis
of the pupil."
In 2005 the Ophthalmology Department of New Zealand's Christchurch Hospital published a review of forty-three studies regarding the use of eye exercises
. They found that "As yet there is no clear scientific evidence published in the mainstream literature supporting the use of eye exercises" to improve visual acuity, and concluded that "their use therefore remains controversial."
was that they "bore no fruit". In regards to the Bates method, he reasoned that "If palming, shifting, and swinging could really cure poor eyesight, glasses would be as obsolete by now as horse-drawn carriages." Others, including philosopher Frank J. Leavitt, have argued that due to Bates' emphasis on relaxation and visualization, application of his principles would depend heavily on each individual, as with martial arts
and yoga
, and that the Bates method is therefore not discredited simply by its failure to become mainstream.
regarding what could be a sight-threatening condition requiring prompt treatment, such as glaucoma
. Also, children with vision problems may require early attention by a professional in order to successfully prevent lazy eye
. Such treatment may include exercises, but which are different from those associated with the Bates method, and parents who subscribe to Bates' ideas may delay seeking conventional care until it is too late. It may further be necessary for a child at risk of developing lazy eye to wear the proper correction.
Recent articles about the method:
Coverage focusing on individual cases:
Non-English works
Alternative medicine
Alternative medicine is any healing practice, "that does not fall within the realm of conventional medicine." It is based on historical or cultural traditions, rather than on scientific evidence....
aimed at improving eyesight
Visual acuity
Visual acuity is acuteness or clearness of vision, which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain....
. Eye-care physician William Horatio Bates (1860–1931) attributed nearly all sight problems to habitual
Habit (psychology)
Habits are routines of behavior that are repeated regularly and tend to occur subconsciously. Habitual behavior often goes unnoticed in persons exhibiting it, because a person does not need to engage in self-analysis when undertaking routine tasks...
strain of the eyes, and felt that glasses
Glasses
Glasses, also known as eyeglasses , spectacles or simply specs , are frames bearing lenses worn in front of the eyes. They are normally used for vision correction or eye protection. Safety glasses are a kind of eye protection against flying debris or against visible and near visible light or...
were harmful and never necessary. Bates self-published a book as well as a magazine (and earlier collaborated with Bernarr MacFadden
Bernarr Macfadden
Bernarr Macfadden was an influential American proponent of physical culture, a combination of bodybuilding with nutritional and health theories...
on a correspondence course) detailing his approach to helping people relax such "strain", and thus, he claimed, improve their sight. His techniques centered around visualization and movement. He placed particular emphasis on imagining black
Black
Black is the color of objects that do not emit or reflect light in any part of the visible spectrum; they absorb all such frequencies of light...
letters and marks, and the movement of such. He also felt that exposing the eyes to sunlight would help alleviate the "strain".
Despite continued anecdotal reports of successful results, including well-publicized support by Aldous Huxley
Aldous Huxley
Aldous Leonard Huxley was an English writer and one of the most prominent members of the famous Huxley family. Best known for his novels including Brave New World and a wide-ranging output of essays, Huxley also edited the magazine Oxford Poetry, and published short stories, poetry, travel...
, Bates' techniques have not been shown objectively
Objectivity (science)
Objectivity in science is a value that informs how science is practiced and how scientific truths are created. It is the idea that scientists, in attempting to uncover truths about the natural world, must aspire to eliminate personal biases, a priori commitments, emotional involvement, etc...
to improve eyesight, and his main physiological proposition – that the eyeball changes shape to maintain focus
Focus (optics)
In geometrical optics, a focus, also called an image point, is the point where light rays originating from a point on the object converge. Although the focus is conceptually a point, physically the focus has a spatial extent, called the blur circle. This non-ideal focusing may be caused by...
– has consistently been contradicted by observation. In 1952, optometry professor Elwin Marg wrote of Bates, “Most of his claims and almost all of his theories have been considered false by practically all visual scientists.” Marg concluded that the Bates method owed its popularity largely to "flashes of clear vision" experienced by many who followed it. Such occurrences have since been determined to most likely be a contact lens
Contact lens
A contact lens, or simply contact, is a lens placed on the eye. They are considered medical devices and can be worn to correct vision, for cosmetic or therapeutic reasons. In 2004, it was estimated that 125 million people use contact lenses worldwide, including 28 to 38 million in the United...
-like effect of moisture on the eye.
Critics of the Bates method not only deny its efficacy, but go on to cite potential negative consequences for those who attempt to follow it, namely that they might overexpose their eyes to sunlight, put themselves and others at risk by not wearing their corrective lenses while driving, or neglect conventional eye care, possibly allowing serious conditions to develop.
Accommodation
AccommodationAccommodation (eye)
Accommodation is the process by which the vertebrate eye changes optical power to maintain a clear image on an object as its distance changes....
is the process by which the eye increases optical power
Optical power
Optical power is the degree to which a lens, mirror, or other optical system converges or diverges light. It is equal to the reciprocal of the focal length of the device. The dioptre is the most common unit of measurement of optical power...
to maintain focus
Focus (optics)
In geometrical optics, a focus, also called an image point, is the point where light rays originating from a point on the object converge. Although the focus is conceptually a point, physically the focus has a spatial extent, called the blur circle. This non-ideal focusing may be caused by...
on the retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
while shifting its gaze to a closer point. The long-standing medical consensus is that this is accomplished by action of the ciliary muscle
Ciliary muscle
The ciliary muscle is a ring of striated smooth muscle in the eye's middle layer that controls accommodation for viewing objects at varying distances and regulates the flow of aqueous humour into Schlemm's canal. It changes the shape of the lens within the eye not the size of the pupil which is...
, a muscle within the eye, which adjusts the curvature of the eye's crystalline lens
Lens (anatomy)
The crystalline lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina. The lens, by changing shape, functions to change the focal distance of the eye so that it can focus on objects at various distances, thus allowing a...
. This explanation is based in the observed effect of atropine
Atropine
Atropine is a naturally occurring tropane alkaloid extracted from deadly nightshade , Jimson weed , mandrake and other plants of the family Solanaceae. It is a secondary metabolite of these plants and serves as a drug with a wide variety of effects...
temporarily preventing accommodation when applied to the ciliary muscle, as well as images reflected on the crystalline lens becoming smaller as the eye shifts focus to a closer point, indicating a change in the lens' shape. Bates rejected this explanation, and in his 1920 book presented photographs which he said showed that the image remained the same size even as the eye shifted focus, concluding from this that the lens was not a factor in accommodation. However, optometrist Philip Pollack in a 1956 work characterized these photographs as "so blurred that it is impossible to tell whether one image is larger than the other", in contrast to later photographs
Timeline of photography technology
Timeline of photography technology* 1822 – Nicéphore Niépce takes the first fixed, permanent photograph, of an engraving of Pope Pius VII, using a non-lens contact-printing "heliographic process", but it was destroyed later; the earliest surviving example is from 1825.* 1826 – Nicéphore Niépce...
which clearly showed a change in the size of the reflected images, just as had been observed since the late nineteenth century.
Bates adhered to a different explanation of accommodation which had already been generally disregarded by the medical community of his time. This model had the muscles surrounding the eyeball
Extraocular muscles
The extraocular muscles are the six muscles that control the movements of the eye . The actions of the extraocular muscles depend on the position of the eye at the time of muscle contraction.-List of muscles:-Importance:...
controlling its focus. In addition to their known function of turning the eye, Bates maintained, they also affect its shape, elongating the eyeball to focus at the near-point or shortening it to focus at a distance. Commenting on this hypothesis in an interview with WebMD
WebMD
WebMD is an American corporation which provides health information services. It was founded in 1996 by Jim Clark and Pavan Nigam as Healthscape, later Healtheon, and then acquired WebMD in 1999 to form Healtheon/WebMD...
, ophthalmologist Richard E. Bensinger stated "When we put drops in the eye to dilate the pupil, they paralyze the focusing muscles. The evidence of the anatomical fallacy is that you can't focus, but your eye can move up and down, left and right. The notion that external muscles affect focusing is totally wrong." Science author John Grant
John Grant (author)
John Grant is a Scottish writer and editor of science fiction, fantasy, and non-fiction. Born as Paul le Page Barnett, Grant has sometimes written under his own name "Paul Barnett" or as "Eve Devereux"...
writes that many animals, such as fishes, accommodate by elongation of the eyeball, "it's just that humans aren't one of those animals."
Laboratory tests have shown that the eyeball is far too rigid to spontaneously change shape to a degree which would be necessary to accomplish what Bates described. Exceedingly small changes in axial length of the eyeball (18.6-19.2 micrometre
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
s) are caused by the action of the ciliary muscle during accommodation. However, these changes are far too small to account for the necessary changes in focus, producing changes of only -0.036 dioptre
Dioptre
A dioptre, or diopter, is a unit of measurement of the optical power of a lens or curved mirror, which is equal to the reciprocal of the focal length measured in metres . It is thus a unit of reciprocal length. For example, a 3-dioptre lens brings parallel rays of light to focus at metre...
s.
Causes of sight problems
Medical professionals characterize refractive errors such as nearsightedness, farsightedness, astigmatism, and presbyopiaPresbyopia
Presbyopia is a condition where the eye exhibits a progressively diminished ability to focus on near objects with age. Presbyopia’s exact mechanisms are not known with certainty; the research evidence most strongly supports a loss of elasticity of the crystalline lens, although changes in the...
(the age-related blurring of near-point vision) as consequences of the eye's shape and other basic anatomy, which there is no evidence that any exercise can alter. Bates, however, believed that these conditions are caused by tension of the muscles surrounding the eyeball, which he believed prevents the eyeball from sufficiently changing shape (per his explanation of accommodation) when gaze is shifted nearer or farther. Bates characterized this supposed muscular tension as the consequence of a "mental strain" to see, the relief of which he claimed would instantly improve sight. He also linked disturbances in the circulation
Circulatory system
The circulatory system is an organ system that passes nutrients , gases, hormones, blood cells, etc...
of blood, which he said is "very largely influenced by thought", not only to refractive errors but also to double vision
Diplopia
Diplopia, commonly known as double vision, is the simultaneous perception of two images of a single object that may be displaced horizontally, vertically, or diagonally in relation to each other...
, crossed-eye
Strabismus
Strabismus is a condition in which the eyes are not properly aligned with each other. It typically involves a lack of coordination between the extraocular muscles, which prevents bringing the gaze of each eye to the same point in space and preventing proper binocular vision, which may adversely...
, lazy eye
Amblyopia
Amblyopia, also known as lazy eye, is a disorder of the visual system that is characterized by a vision deficiency in an eye that is otherwise physically normal, or out of proportion to associated structural abnormalities of the eye...
, and to more serious eye conditions such as cataract
Cataract
A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...
s and glaucoma
Glaucoma
Glaucoma is an eye disorder in which the optic nerve suffers damage, permanently damaging vision in the affected eye and progressing to complete blindness if untreated. It is often, but not always, associated with increased pressure of the fluid in the eye...
. His therapies were based on these assumptions.
Bates felt that corrective lenses, which he characterized as "eye crutches", are an impediment to curing poor vision. In his view, "strain" would increase as the eyes adjust to the correction in front of them. He thus recommended that glasses
Glasses
Glasses, also known as eyeglasses , spectacles or simply specs , are frames bearing lenses worn in front of the eyes. They are normally used for vision correction or eye protection. Safety glasses are a kind of eye protection against flying debris or against visible and near visible light or...
be discarded by anyone applying his method.
Treatments
In his writings, Bates discussed several techniques which he claimed helped patients to improve their sight. He wrote that "The ways in which people strain to see are infinite, and the methods used to relieve the strain must be almost equally varied", emphasizing that no single approach would work for everyone. His techniques were all designed to help disassociate this "strain" from seeing and thereby achieve "central fixation", or seeing what is in the central point of vision without staring. He asserted that "all errors of refraction and all functional disturbances of the eye disappear when it sees by central fixation" and that other conditions were often relieved as well.Palming
Eigengrau
Eigengrau , also called Eigenlicht , dark light, or brain gray, is the color seen by the eye in perfect darkness...
or "dark light". In fact, even in conditions of perfect darkness, as inside a cave, neurons at every level of the visual system
Visual system
The visual system is the part of the central nervous system which enables organisms to process visual detail, as well as enabling several non-image forming photoresponse functions. It interprets information from visible light to build a representation of the surrounding world...
produce random background activity that is interpreted by the brain as patterns of light and color.
Visualization
Bates placed importance on mental imageMental image
A mental image is an experience that, on most occasions, significantly resembles the experience of perceiving some object, event, or scene, but occurs when the relevant object, event, or scene is not actually present to the senses...
s, as he felt relaxation was the key to clarity of imagination as well as of actual sight. He claimed that one's poise could be gauged by the visual memory of black; that the darker it appeared in the mind, and the smaller the area of black which could be imagined, the more relaxed one was at the moment. He recommended that patients think of the top letter from an eye chart
Snellen chart
A Snellen chart is an eye chart used by eye care professionals and others to measure visual acuity. Snellen charts are named after the Dutch ophthalmologist Herman Snellen who developed the chart during 1862...
and then visualize progressively smaller black letters, and eventually a period or comma. But he emphasized his view that the clear visual memory of black "cannot be attained by any sort of effort", stating that "the memory is not the cause of the relaxation, but must be preceded by it", and cautioned against "concentrating" on black, as he regarded an attempt to "think of one thing only" as a strain.
While Bates preferred to have patients imagine something black, he also reported that some found objects of other colors easiest to visualize, and thus were benefited most by remembering those, because, he asserted, "the memory can never be perfect unless it is easy". Skeptics reason that the only benefit to eyesight gained from such techniques is itself imagined, and point out that familiar objects, including letters on an eye chart, can be recognized even when they appear less than clear.
Movement
Bates felt that the manner of eye movement affected the sight. He suggested "shifting", or moving the eyes back and forth to get an illusion of objects "swinging" in the opposite direction. He believed that the smaller the area over which the "swing" was experienced, the greater was the benefit to sight. He also indicated that it was usually helpful to close the eyes and imagine something "swinging". By alternating actual and mental shifting over an image, Bates wrote, many patients were quickly able to shorten the "shift" to a point where they could "conceive and swing a letter the size of a period in a newspaper." One who mastered this would attain the "universal swing", Bates believed.Perhaps finding Bates' concepts of "shifting" and "swinging" too complicated, some proponents of vision improvement, such as Bernarr Macfadden
Bernarr Macfadden
Bernarr Macfadden was an influential American proponent of physical culture, a combination of bodybuilding with nutritional and health theories...
, suggested simply moving the eyes up and down, from side to side, and shifting one's gaze between a near-point and a far-point.
Sunning
Sungazing
Sungazing is a practice that includes gazing at the sun for nourishment or as a spiritual practice.Looking into the sun is dangerous, and can cause solar retinopathy and lead to permanent eye damage or blindness.-Purpose:...
—this is at variance with the well-known risk of eye damage
Solar retinopathy
Solar retinopathy is damage to the eye's retina, particularly the macula, from prolonged exposure to solar radiation. It usually occurs due to staring at the sun or viewing a solar eclipse.-Pathophysiology:...
which can result from direct sunlight observation.
Bates cautioned that, just as one should not attempt to run a marathon without training, one should not immediately look directly at the sun, but he suggested that it could be worked up to. He acknowledged that looking at the sun could have ill effects, but characterized them as being "always temporary" and in fact the effects of strain in response to sunlight. He wrote that he had cured people who believed that the sun had caused them permanent eye damage. In his magazine, Bates later suggested exposing only the white part of the eyeball to direct sunlight, and only for seconds at a time, after allowing the sun to shine on closed eyelids for a longer period.
Eventually Bates concluded that the practice of sunning should only be done with closed eyelids. Posthumous publications of Bates' book omitted mention of the supposed benefits from direct sunlight shining on open eyes.
Results
The purported benefits of Bates' techniques are generally anecdotalAnecdotal evidence
The expression anecdotal evidence refers to evidence from anecdotes. Because of the small sample, there is a larger chance that it may be true but unreliable due to cherry-picked or otherwise unrepresentative of typical cases....
, and their supposed effectiveness in improving eyesight has not been substantiated by medical research. Several of Bates' techniques, including "sunning", "swinging", and "palming", were combined with healthy changes to diet and exercise in a 1983 randomized controlled trial
Randomized controlled trial
A randomized controlled trial is a type of scientific experiment - a form of clinical trial - most commonly used in testing the safety and efficacy or effectiveness of healthcare services or health technologies A randomized controlled trial (RCT) is a type of scientific experiment - a form of...
of myopic children in India. After 6 months, the experimental groups "did not show any statistically significant difference in refractive status", but the children in the treatment group "subjectively
Subjectivity
Subjectivity refers to the subject and his or her perspective, feelings, beliefs, and desires. In philosophy, the term is usually contrasted with objectivity.-Qualia:...
... felt relieved of eye strain and other symptoms."
It has been argued, such as by philosopher Frank J. Leavitt, that the method which Bates described would be difficult to test
Testability
Testability, a property applying to an empirical hypothesis, involves two components: the logical property that is variously described as contingency, defeasibility, or falsifiability, which means that counterexamples to the hypothesis are logically possible, and the practical feasibility of...
scientifically due to his emphasis on relaxation and visualization. Leavitt asked "How can we tell whether someone has relaxed or imagined something, or just thinks that he or she has imagined it?" In regards to the possibility of a placebo trial, Leavitt commented "I cannot conceive of how we could put someone in a situation where he thinks he has imagined something while we know that he has not."
After Bates
After Bates died in 1931, his methods of treatment were continued by his widow Emily and other associates, some of whom incorporated exercises and dietary recommendations. Most subsequent proponents did not stand by Bates' explanation of how the eye focuses mechanically, but nonetheless maintained that relieving a habitual "strain" was the key to improving sight.Margaret Darst Corbett
Margaret Darst Corbett first met Dr. Bates when she consulted him about her husband’s eyesight. She became his pupil, and eventually taught his method at her School of Eye Education in Los Angeles. She was of the stated belief that "the optic nerve is really part of the brain, and vision is nine-tenths mental and one-tenth only physical."In late 1940, Corbett and her assistant were charged with violations of the Medical Practice Act of California for treating eyes without a licence. At the trial, many of her students testified on her behalf, describing in detail how she had enabled them to discard their glasses. One witness testified that he had been almost blind from cataracts, but that, after working with Corbett, his vision had improved to such an extent that for the first time he could read for eight hours at a stretch without glasses. Corbett explained in court that she was practicing neither optometry
Optometry
Optometry is a health care profession concerned with eyes and related structures, as well as vision, visual systems, and vision information processing in humans. Optometrists, or Doctors of Optometry, are state licensed medical professionals trained to prescribe and fit lenses to improve vision,...
nor ophthalmology
Ophthalmology
Ophthalmology is the branch of medicine that deals with the anatomy, physiology and diseases of the eye. An ophthalmologist is a specialist in medical and surgical eye problems...
and represented herself not as a doctor but only as an “instructor of eye training”. Describing her method she said "We turn vision on by teaching the eyes to shift. We want the sense of motion to relieve staring, to end the fixed look. We use light to relax the eyes and to accustom them to the sun."
The trial attracted widespread interest, as did the “not guilty” verdict. The case spurred a bill in the Californian State Legislature which would have then made such vision education illegal without an optometric or medical licence. After a lively campaign in the media, the bill was rejected.
Case of Huxley
Aldous Huxley
Aldous Leonard Huxley was an English writer and one of the most prominent members of the famous Huxley family. Best known for his novels including Brave New World and a wide-ranging output of essays, Huxley also edited the magazine Oxford Poetry, and published short stories, poetry, travel...
. At the age of sixteen Huxley had an attack of keratitis
Keratitis
Keratitis is a condition in which the eye's cornea, the front part of the eye, becomes inflamed. The condition is often marked by moderate to intense pain and usually involves impaired eyesight.-Types:...
, which, after an 18-month period of near-blindness, left him with one eye just capable of light perception and the other with an unaided Snellen fraction of 10/200. This was mainly due to opacities in both cornea
Cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Together with the lens, the cornea refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is...
s, complicated by hyperopia
Hyperopia
Hyperopia, also known as farsightedness, longsightedness or hypermetropia, is a defect of vision caused by an imperfection in the eye , causing difficulty focusing on near objects, and in extreme cases causing a sufferer to be unable to focus on objects at any distance...
and astigmatism
Astigmatism
An optical system with astigmatism is one where rays that propagate in two perpendicular planes have different foci. If an optical system with astigmatism is used to form an image of a cross, the vertical and horizontal lines will be in sharp focus at two different distances...
. He was able to read only if he wore thick glasses and dilated his better pupil with atropine
Atropine
Atropine is a naturally occurring tropane alkaloid extracted from deadly nightshade , Jimson weed , mandrake and other plants of the family Solanaceae. It is a secondary metabolite of these plants and serves as a drug with a wide variety of effects...
, to allow that eye to see around an opacity in the center of the cornea.
In 1939, at the age of 45 and with eyesight which continued to deteriorate, he happened to hear of the Bates method and sought the help of Margaret Corbett, who gave him regular lessons. Three years later he wrote The Art of Seeing
The Art of Seeing
The Art of Seeing is a 1942 book by Aldous Huxley, which details his experience with and views on the controversial Bates method, which Huxley believed improved his eyesight.-Huxley’s own sight:...
, in which he related: "Within a couple of months I was reading without spectacles and, what was better still, without strain and fatigue... At the present time, my vision, though very far from normal, is about twice as good as it used to be when I wore spectacles". Describing the process, Huxley wrote that "Vision is not won by making an effort to get it: it comes to those who have learned to put their minds and eyes into a state of alert passivity, of dynamic relaxation." He expressed indifference regarding the veracity of Bates' explanation of how the eye focuses, stating that "my concern is not with the anatomical mechanism of accommodation, but with the art of seeing".
His case generated wide publicity as well as scrutiny. Ophthalmologist Walter B. Lancaster, for example, suggested in 1944 that Huxley had "learned how to use what he has to better advantage" by training the "cerebral part of seeing", rather than actually improving the quality of the image on the retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
.
In 1952, ten years after writing The Art of Seeing, Huxley spoke at a Hollywood banquet, wearing no glasses and, according to Bennett Cerf
Bennett Cerf
Bennett Alfred Cerf was a publisher and co-founder of Random House. Cerf was also known for his own compilations of jokes and puns, for regular personal appearances lecturing across the United States, and for his television appearances in the panel game show What's My Line?.-Biography:Bennett Cerf...
, apparently reading his paper from the lectern without difficulty. In Cerf's words:
Then suddenly he faltered—and the disturbing truth became obvious. He wasn't reading his address at all. He had learned it by heart. To refresh his memory he brought the paper closer and closer to his eyes. When it was only an inch or so away he still couldn't read it, and had to fish for a magnifying glass in his pocket to make the typing visible to him. It was an agonizing moment.
In response to this, Huxley wrote "I often do use magnifying glasses where conditions of light are bad, and have never claimed to be able to read except under very good conditions." This underscored that he had not regained anything close to normal vision, and in fact never claimed that he had.
Modern variants
"Natural vision correction" or "natural vision improvement" continues to be marketed by practitioners offering individual instruction, many of who have no medical or optometric credentials. Most base their approach in the Bates method, though some also integrate vision therapyVision therapy
Vision therapy, also known as visual training, vision training, or visual therapy, is a broad group of techniques aimed at correcting and improving binocular, oculomotor, visual processing, and perceptual disorders."-Historical development:...
techniques. There are also many self-help
Self-help
Self-help, or self-improvement, is a self-guided improvement—economically, intellectually, or emotionally—often with a substantial psychological basis. There are many different self-help movements and each has its own focus, techniques, associated beliefs, proponents and in some cases, leaders...
books and programs, which have not been subjected to randomized controlled trials, aimed at improving eyesight naturally. Purveyors of such approaches argue that they lack the funds to formally test them.
The heavily advertised "See Clearly Method
See Clearly Method
The See Clearly Method is an eye exercise program that was marketed as an alternative to the use of glasses, contact lenses, and eye surgery to improve vision. Sales were halted by legal action in 2006. The method is not supported by basic science, and no research studies were conducted prior to...
" (of which sales were halted by a court order in November 2006, in response to what were found to be dishonest marketing practices) included "palming" and "light therapy", both adapted from Bates. The creators of the program, however, emphasized that they did not endorse Bates' approach overall.
In his 1992 book The Bates Method, A Complete Guide to Improving Eyesight—Naturally, "Bates method teacher" Peter Mansfield was very critical of eye care professional
Eye care professional
An eye care professional is an individual who provides a service related to the eyes or vision. It is a general term that can refer to any healthcare worker involved in eye care, from one with a small amount of post-secondary training to practitioners with a doctoral level of education.-Current...
s for prescribing corrective lenses. He recommended most of Bates' techniques to improve vision, but omitted sungazing. The book included accounts of twelve instances of eyesight improving, but did not report any measurements of refractive error
Refractive error
A refractive error, or refraction error, is an error in the focusing of light by the eye and a frequent reason for reduced visual acuity.-Classification:...
.
Czech native John Slavicek claims to have created an "eye cure" that improves eyesight in three days, borrowing from ancient yogic eye exercises, visualizations from the Seth Material, and the Bates method. Although he has testimonials from his neighbor and others, several of his students indicate that he has greatly exaggerated their cases. Slavicek's self-published manual, Yoga for the Eyes, was rejected by an ophthalmologist who evaluated it, and evinced no interest from the World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...
and St. Erik's Eye Foundation in Sweden as he had not conducted double-blind
Double-blind
A blind or blinded experiment is a scientific experiment where some of the people involved are prevented from knowing certain information that might lead to conscious or subconscious bias on their part, invalidating the results....
tests.
Claimed success
As evidence for the effectiveness of the Bates method, proponents point to the many accounts of people allegedly having improved their eyesight by applying it. While these anecdotes may be told and passed on in good faithGood faith
In philosophy, the concept of Good faith—Latin bona fides “good faith”, bona fide “in good faith”—denotes sincere, honest intention or belief, regardless of the outcome of an action; the opposed concepts are bad faith, mala fides and perfidy...
, several potential explanations exist for the phenomena reported other than a genuine reversal of a refractive error
Refractive error
A refractive error, or refraction error, is an error in the focusing of light by the eye and a frequent reason for reduced visual acuity.-Classification:...
due to the techniques practiced:
- Some cases of nearsightedness are recognized as due to a transient spasm of the ciliary muscle, rather than a misshapen eyeball. These are classed as pseudomyopiaPseudomyopiaPseudomyopia refers to an intermittent and temporary shift in refraction of the eye towards myopia, in which the focusing of light in front of the retina is due to a transient spasm of the ciliary muscle causing an increase in the refractive power of the eye...
, of which spontaneous reversal may account for some reports of improvement. - Research has confirmed that when nearsighted subjects remove their corrective lenses, over time there is a limited improvement (termed "blur adaptation") in their unaided visual resolution, even though autorefraction indicates no corresponding change in refractive error. This is believed to occur due to adjustments made in the visual systemVisual systemThe visual system is the part of the central nervous system which enables organisms to process visual detail, as well as enabling several non-image forming photoresponse functions. It interprets information from visible light to build a representation of the surrounding world...
. One who has been practicing Bates' techniques and notices such improvement may not realize that simply leaving the glasses off would have had the same effect, which may be especially pronounced if the prescriptionEyeglass prescriptionAn eyeglass prescription is an order written by an eyewear prescriber, such as an optometrist or ophthalmologist, that specifies the value of all parameters the prescriber has deemed necessary to construct and/or dispense corrective lenses appropriate for a patient.If an examination indicates that...
was too strong to begin with. - Visual acuity is affected by the size of the pupilPupilThe pupil is a hole located in the center of the iris of the eye that allows light to enter the retina. It appears black because most of the light entering the pupil is absorbed by the tissues inside the eye. In humans the pupil is round, but other species, such as some cats, have slit pupils. In...
. When it constrictsMiosisMiosis is the constriction of the pupil of the eye to two millimeters or less...
(such as in response to an increase in light), the quality of focus will improve significantly, at the cost of a reduced ability to see in dim light. This is known as the "pinhole effect". - Some eye defects may naturally change for the better with age or in cycles (ophthalmologist Stewart Duke-Elder suggested that this is what happened with Aldous Huxley). A cataractCataractA cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...
when first setting in sometimes results in much improved eyesight for a short time. One who happens to have been practicing the Bates method will likely credit it for any improvement experienced regardless of the actual cause. - Some studies have suggested that a learned ability to interpret blurred images may account for perceived improvements in eyesight. Ophthalmologist Walter B. Lancaster had this to say: "Since seeing is only partly a matter of the image on the retina and the sensation it produces, but is in still larger part a matter of the cerebral processes of synthesis, in which memories play a principal role, it follows that by repetition, by practice, by exercises, one builds up a substratum of memories useful for the interpretation of sensations and facilitates the syntheses which are the major part of seeing." Lancaster faulted ophthalmologists in general for neglecting the role of the brain in the process of seeing, "leaving to irregular, half-trained workers the cultivation of that field".
"Flashes of clear vision"
Bates method enthusiasts often report experiencing "flashes" of clear vision, in which eyesight momentarily becomes much sharper, but then reverts back to its previous state. Such flashes are not the result of squinting, and can occur in one eye at a time or in both eyes at once. Observation has suggested that both the quality and duration of such flashes can be increased with practice, with some subjects holding a substantial improvement for several minutes. Tests of such subjects have found that the temporary improvement in visual acuity is real, but per retinoscopyRetinoscopy
Retinoscopy is a technique to obtain an objective measurement of the refractive error of a patient's eyes. The examiner uses a retinoscope to shine light into the patient's eye and observes the reflection off the patient's retina...
is not due to any change in refractive error
Refractive error
A refractive error, or refraction error, is an error in the focusing of light by the eye and a frequent reason for reduced visual acuity.-Classification:...
. A 1982 study concluded that such occurrences are best explained as a contact lens
Contact lens
A contact lens, or simply contact, is a lens placed on the eye. They are considered medical devices and can be worn to correct vision, for cosmetic or therapeutic reasons. In 2004, it was estimated that 125 million people use contact lenses worldwide, including 28 to 38 million in the United...
-like effect of moisture on the eye, based on increased tear action exhibited by 15 out of 17 subjects who experienced such improvement.
General research
In 2004 the American Academy of OphthalmologyAmerican Academy of Ophthalmology
The American Academy of Ophthalmology is the largest national membership medical association of ophthalmologists–medical doctors specializing in eye care and surgery including medical, surgical and optical care. More than 90 percent of practicing U.S. Eye M.D.s are Academy members, and the...
(AAO) published a review of various research regarding "visual training", which consisted of "eye exercises, muscle relaxation techniques, biofeedback, eye patches, or eye massages", "alone or in combinations". No evidence was found that such techniques could objectively
Objectivity (science)
Objectivity in science is a value that informs how science is practiced and how scientific truths are created. It is the idea that scientists, in attempting to uncover truths about the natural world, must aspire to eliminate personal biases, a priori commitments, emotional involvement, etc...
benefit eyesight, though some studies noted changes, both positive and negative, in the visual acuity
Visual acuity
Visual acuity is acuteness or clearness of vision, which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain....
of nearsighted subjects as measured by a Snellen chart
Snellen chart
A Snellen chart is an eye chart used by eye care professionals and others to measure visual acuity. Snellen charts are named after the Dutch ophthalmologist Herman Snellen who developed the chart during 1862...
. In some cases noted improvements were maintained at subsequent follow-ups. However, these results were not seen as actual reversals of nearsightedness, and were attributed instead to factors such as "improvements in interpreting blurred images, changes in mood or motivation, creation of an artificial contact lens by tear film changes, or a pinhole effect from miosis
Miosis
Miosis is the constriction of the pupil of the eye to two millimeters or less...
of the pupil."
In 2005 the Ophthalmology Department of New Zealand's Christchurch Hospital published a review of forty-three studies regarding the use of eye exercises
Eye exercises
Orthoptics is a discipline dealing with the diagnosis and treatment of defective eye movement and coordination , binocular vision, and amblyopia by eye care professionals...
. They found that "As yet there is no clear scientific evidence published in the mainstream literature supporting the use of eye exercises" to improve visual acuity, and concluded that "their use therefore remains controversial."
Dead-end
A frequent criticism of the Bates method is that it has remained relatively obscure, which is seen as proof that it is not truly effective. Writer Alan M. MacRobert concluded in a 1979 article that the "most telling argument against the Bates system" and other alternative therapiesAlternative medicine
Alternative medicine is any healing practice, "that does not fall within the realm of conventional medicine." It is based on historical or cultural traditions, rather than on scientific evidence....
was that they "bore no fruit". In regards to the Bates method, he reasoned that "If palming, shifting, and swinging could really cure poor eyesight, glasses would be as obsolete by now as horse-drawn carriages." Others, including philosopher Frank J. Leavitt, have argued that due to Bates' emphasis on relaxation and visualization, application of his principles would depend heavily on each individual, as with martial arts
Martial arts
Martial arts are extensive systems of codified practices and traditions of combat, practiced for a variety of reasons, including self-defense, competition, physical health and fitness, as well as mental and spiritual development....
and yoga
Yoga
Yoga is a physical, mental, and spiritual discipline, originating in ancient India. The goal of yoga, or of the person practicing yoga, is the attainment of a state of perfect spiritual insight and tranquility while meditating on Supersoul...
, and that the Bates method is therefore not discredited simply by its failure to become mainstream.
Corrective lenses and safety
Discarding one's corrective lenses, as Bates recommended, or wearing lenses weaker than one's prescribed correction, as some Bates method advocates suggest, poses a potential safety hazard in certain situations, especially when one is operating a motor vehicle. However, most teachers of the Bates method caution that when driving, one should wear the correction legally required.Avoidance of conventional treatment
One of the greatest potential dangers of faith in the Bates method is that a believer may be disinclined to seek medical adviceEye examination
An eye examination is a battery of tests performed by an ophthalmologist, optometrist, or orthoptist assessing vision and ability to focus on and discern objects, as well as other tests and examinations pertaining to the eyes....
regarding what could be a sight-threatening condition requiring prompt treatment, such as glaucoma
Glaucoma
Glaucoma is an eye disorder in which the optic nerve suffers damage, permanently damaging vision in the affected eye and progressing to complete blindness if untreated. It is often, but not always, associated with increased pressure of the fluid in the eye...
. Also, children with vision problems may require early attention by a professional in order to successfully prevent lazy eye
Amblyopia
Amblyopia, also known as lazy eye, is a disorder of the visual system that is characterized by a vision deficiency in an eye that is otherwise physically normal, or out of proportion to associated structural abnormalities of the eye...
. Such treatment may include exercises, but which are different from those associated with the Bates method, and parents who subscribe to Bates' ideas may delay seeking conventional care until it is too late. It may further be necessary for a child at risk of developing lazy eye to wear the proper correction.
External links
Historical writings:- Library of public domain works related to the Bates method.
- Bates' first published article about his method of treating eyesight, American Journal of Ophthalmology, 1891, pp. 181–183.
Recent articles about the method:
- Gale Encyclopedia of Alternative Medicine–Bates Method entry by Lisa Frick.
Coverage focusing on individual cases:
Non-English works
- Russian book on the Bates method—Automatically translated by Google