These diagrams are 19th and 20th century attempts to systematize colours and describe how the human eye perceives them. In the late 18th century, scholars began to develop colour theory according to the understanding that three primary colours – red, yellow, and blue – could be combined to create all others; these hypotheses would be instrumental in forming early theories of colour vision and the science of perception.
Although Sir Isaac Newton and Da Vinci both developed theories of colour, the German poet Goethe organized colours into the “wheel” we know today in his Theory of Colours in 1810. Albert Munsell developed his Color System which was later adopted by the US Bureau of Standards later in the century. Of course, these standards would influence not only contemporary explorations of the science of vision, but the creative disciplines of art and design as well. (artandsciencejournal)
Theory of Colours
Theory of Colours (original German title Zur Farbenlehre) is a work by Johann Wolfgang von Goethe about the poet's views on the nature of colours and how these are perceived by humans. Published in 1810, it contains some of the earliest published descriptions of phenomena such as coloured shadows, refraction, and chromatic aberration.
The work originated in Goethe's occupation with painting and mainly exerted an influence onto the arts (Philipp Otto Runge, J. M. W. Turner, the Pre-Raphaelites, Wassily Kandinsky).
Although Goethe's work was rejected by physicists, a number of philosophers and physicists have concerned themselves with it, including Thomas Johann Seebeck, Arthur Schopenhauer (see: On Vision and Colors), Hermann von Helmholtz, Rudolf Steiner, Ludwig Wittgenstein, Werner Heisenberg, Kurt Gödel, and Mitchell Feigenbaum.
In his book, Goethe provides a general exposition of how colour is perceived in a variety of circumstances, and considers Isaac Newton's observations to be special cases. Goethe's concern was not so much with the analytic measurement of colour phenomenon, as with the qualities of how phenomena are perceived. Philosophers have come to understand the distinction between the optical spectrum, as observed by Newton, and the phenomenon of human colour perception as presented by Goethe - a subject analyzed at length by Wittgenstein in his exegesis of Goethe in Remarks on Colour.
Historical background
At Goethe's time, it was generally acknowledged that, as Isaac Newton had shown in his Opticks in 1704, colourless (white) light is split up into its component colours when directed through a prism.Along with the rest of the world I was convinced that all the colours are contained in the light; no one had ever told me anything different, and I had never found the least cause to doubt it, because I had no further interest in the subject. But how I was astonished, as I looked at a white wall through the prism, that it stayed white! That only where it came upon some darkened area, it showed some colour, then at last, around the window sill all the colours shone... It didn't take long before I knew here was something significant about colour to be brought forth, and I spoke as through an instinct out loud, that the Newtonian teachings were false.
—Goethe
Goethe's starting point was the supposed discovery of how Newton erred in the prismatic experiment,[5] and by 1793 Goethe had formulated his arguments against Newton in the essay "Über Newtons Hypothese der diversen Refrangibilität" ("On Newton's hypothesis of diverse refrangibility").
As Goethe notes in the historical section, Louis Bertrand Castel had already published a criticism of Newton's spectral description of prismatic colour in 1740[7] in which he observed that the sequence of colours split by a prism depended on the distance from the prism — and that Newton was looking at a special case.
"Whereas Newton observed the colour spectrum cast on a wall at a fixed distance away from the prism, Goethe observed the cast spectrum on a white card which was progressively moved away from the prism... As the card was moved away, the projected image elongated, gradually assuming an elliptical shape, and the coloured images became larger, finally merging at the centre to produce green. Moving the card farther led to the increase in the size of the image, until finally the spectrum described by Newton in the Opticks was produced... The image cast by the refracted beam was not fixed, but rather developed with increasing distance from the prism. Consequently, Goethe saw the particular distance chosen by Newton to prove the second proposition of the Opticks as capriciously imposed." (Alex Kentsis, Between Light and Eye)
By 1794, Goethe began to sense more and more strongly the meaning of the physiological side of colours. Announcing the publication of the Theory of Colours, he says:
The theory we set up against this begins with colourless light, and avails itself of outward conditions, to produce coloured phenomena; but it concedes worth and dignity to these conditions. It does not arrogate to itself developing colours from the light, but rather seeks to prove by numberless cases that colour is produced by light as well as by what stands against it.
—Goethe
In the preface to the Theory of Colours, Goethe explained that he tried to apply the principle of polarity, in the work – a proposition that belonged to his earliest convictions and was constitutive of his entire study of nature.
Goethe's theory
Goethe's theory of the origin of the spectrum isn't a theory of its origin that has proved unsatisfactory; it is really not a theory at all. Nothing can be predicted by means of it. It is, rather, a vague schematic outline, of the sort we find in James's psychology. There is no experimentum crucis for Goethe's theory of colour.
—Ludwig Wittgenstein, Remarks on Colour
It is hard to present Goethe's "theory", since he refrains from setting up any actual theory; he says, "its intention is to portray rather than explain" (Scientific Studies). Instead of setting up models and explanations, Goethe collected specimens — he was responsible for the meteorological collections of Jena University. By the time of his death, he had amassed over 17,800 minerals in his personal collection — the largest in all of Europe. He took the same approach to colour — instead of narrowing and isolating things to a single experimentum crucius, he sought to gain as much breadth for his understanding as possible by developing a wide range of experiments through which he wished to reveal the essential character of colour (the UR phenomena) — without having to resort to explanation and theories about the perceived phenomena such as 'wavelength' or 'particle'.
"The crux of his color theory is its experiential source: rather than impose theoretical statements, Goethe sought to allow light and color to be displayed in an ordered series of experiments that readers could experience for themselves." (Seamon, 1998). According to Goethe, "Newton's error.. was trusting math over the sensations of his eye." (Jonah Lehrer, 2006).
To stay true to the perception without resort to explanation was the essence of Goethe's method. What he provided was really not so much a theory, as a rational description of colour. For Goethe, "the highest is to understand that all fact is really theory. The blue of the sky reveals to us the basic law of color. Search nothing beyond the phenomena, they themselves are the theory."
[Goethe] delivered in full measure what was promised by the title of his excellent work: Data for a Theory of Color. They are important, complete, and significant data, rich material for a future theory of color. He has not, however, undertaken to furnish the theory itself; hence, as he himself remarks and admits on page xxxix of the introduction, he has not furnished us with a real explanation of the essential nature of color, but really postulates it as a phenomenon, and merely tells us how it originates, not what it is. The physiological colors ... he represents as a phenomenon, complete and existing by itself, without even attempting to show their relation to the physical colors, his principal theme. ... it is really a systematic presentation of facts, but it stops short at this.
—Schopenhauer, On Vision and Colors, Introduction
Goethe outlines his method in the essay, The experiment as mediator between subject and object (1772). It underscores his experiential standpoint. "The human being himself, to the extent that he makes sound use of his senses, is the most exact physical apparatus that can exist." (Goethe, Scientific Studies)
Light and darkness
Unlike his contemporaries, Goethe didn't see darkness as an absence of light, but rather as polar to and interacting with light; colour resulted from this interaction of light and shadow. For Goethe, light is "the simplest most undivided most homogenous being that we know. Confronting it is the darkness" (Letter to Jacobi).
...they maintained that shade is a part of light. It sounds absurd when I express it; but so it is: for they said that colours, which are shadow and the result of shade, are light itself.
—Johann Eckermann, Conversations of Goethe, entry: January 4, 1824; trans. Wallace Wood
Based on his experiments with turbid media, Goethe characterized colour as arising from the dynamic interplay of darkness and light. Rudolf Steiner, the science editor for the Kurschner edition of Goethe's works, gives the following analogy:
Goethe writes:
Yellow is a light which has been dampened by darkness Blue is a darkness weakened by light.
Experiments with turbid media
The action of turbid media was to Goethe the ultimate fact — the Urphänomen — of the world of colours.
—John Tyndall, 1880
Goethe's studies of colour began with experiments which examined the effects of turbid media, such as air, dust, and moisture on the perception of light and dark. The poet observed that light seen through a turbid medium appears yellow, and darkness seen through an illuminated medium appears blue.
The highest degree of light, such as that of the sun... is for the most part colourless. This light, however, seen through a medium but very slightly thickened, appears to us yellow. If the density of such a medium be increased, or if its volume become greater, we shall see the light gradually assume a yellow-red hue, which at last deepens to a ruby colour. If on the other hand darkness is seen through a semi-transparent medium, which is itself illumined by a light striking on it, a blue colour appears: this becomes lighter and paler as the density of the medium is increased, but on the contrary appears darker and deeper the more transparent the medium becomes: in the least degree of dimness short of absolute transparence, always supposing a perfectly colourless medium, this deep blue approaches the most beautiful violet.
—Goethe, Theory of Colours, pp. 150–151
He then proceeds with numerous experiments, systematically observing the effects of rarefied mediums such as dust, air, and moisture on the perception of colour.
Boundary conditions
When viewed through a prism, the orientation of a light-dark boundary with respect to the prism's axis is significant. With white above a dark boundary, we observe the light extending a blue-violet edge into the dark area; whereas dark above a light boundary results in a red-yellow edge extending into the light area.
Goethe was intrigued by this difference. He felt that this arising of colour at light-dark boundaries was fundamental to the creation of the spectrum (which he considered to be a compound phenomenon).
Varying the experimental conditions by using different shades of grey shows that the intensity of coloured edges increases with boundary contrast.
Light and dark spectra
Since the colour phenomenon relies on the adjacency of light and dark, there are two ways to produce a spectrum: with a light beam in a dark room, and with a dark beam (i.e. a shadow) in a light room.
Goethe recorded the sequence of colours projected at various distances from a prism for both cases (see Plate IV, Theory of Colours). In both cases, he found that the yellow and blue edges remain closest to the side which is light, and red and violet edges remain closest to the side which is dark. At a certain distance, these edges overlap – and we obtain Newton's spectrum. When these edges overlap in a light spectrum, green results; when they overlap in a dark spectrum, magenta results.
With a light spectrum, coming out of the prism, one sees a shaft of light surrounded by dark. We find yellow-red colours along the top edge, and blue-violet colours along the bottom edge. The spectrum with green in the middle arises only where the blue-violet edges overlap the yellow-red edges.
With a dark spectrum (i.e. a shadow surrounded by light), we find violet-blue along the top edge, and red-yellow along the bottom edge – where these edges overlap, we find magenta.
Goethe's colour wheel
When the eye sees a colour it is immediately excited and it is its nature, spontaneously and of necessity, at once to produce another, which with the original colour, comprehends the whole chromatic scale.— Goethe, Theory of Colours
Goethe anticipated Ewald Hering's Opponent process theory by proposing a symmetric colour wheel. He writes, "The chromatic circle... [is] arranged in a general way according to the natural order... for the colours diametrically opposed to each other in this diagram are those which reciprocally evoke each other in the eye. Thus, yellow demands violet; orange, blue; red, green; and vice versa: thus... all intermediate gradations reciprocally evoke each other; the simpler colour demanding the compound, and vice versa. (Goethe, Theory of Colours).
Goethe expressed his understanding of the light and dark spectra in including magenta in his colour wheel. Whereas for Newton magenta was an 'extraspectral' colour, for Goethe magenta was a natural result of violet and red being mixed in a dark spectrum (see top of colour wheel), just as green resulted from the mixing of blue and yellow in the light spectrum (bottom of colour wheel).
"For Newton, only spectral colors could count as fundamental. By contrast, Goethe's more empirical approach led him to recognize the essential role of (nonspectral) magenta in a complete color circle, a role that it still has in all modern color systems."
Goethe also investigated the effects of colour on the physiology of individuals in an art of colour psychology. Because of this, he included aesthetic qualities in his colour wheel — associating Red with the beautiful, orange with the noble, yellow to the good, green to the useful, blue to the mean, and violet to the unnecessary.
Newton and Goethe
Due to their different approaches to a common subject, many misunderstandings have arisen between Newton's mathematical understanding of optics, and Goethe's experiential approach.
Because Newton understands white light to be composed of individual colours, and Goethe sees colour arising from the interaction of light and dark, they come to different conclusions on the question: is the optical spectrum a primary or a compound phenomenon?
For Newton, the prism is immaterial to the existence of colour, as all the colours already exist in white light, and the prism merely fans them out according to their refrangibility. Goethe sought to show that, as a turbid medium, the prism was an integral factor in the arising of colour.
Whereas Newton narrowed the beam of light in order to isolate the phenomenon, Goethe observed that with a wider aperture, there was no spectrum. He saw only reddish-yellow edges and blue-cyan edges with white between them, and the spectrum arose only where these edges came close enough to overlap. For him, the spectrum could be explained by the simpler phenomena of colour arising from the interaction of light and dark edges.
History and influence
The first edition of the Farbenlehre was printed at the Cotta’schen Verlagsbuchhandlung on May 16, 1810, with 250 copies on grey paper and 500 copies on white paper. It contained three sections: i) a didactic section in which Goethe presents his own observations, ii) a polemic section in which he makes his case against Newton, and iii) a historical section.
From its publication, the book was controversial for its stance against Newton. So much so, that when Charles Eastlake translated the text into English in 1840, he omitted the content of Goethe's polemic against Newton.
Significantly (and regrettably), only the 'Didactic' colour observations appear in Eastlake's translation. In his preface, Eastlake explains that he deleted the historical and entoptic parts of the book because they 'lacked scientific interest', and censored Goethe's polemic because the 'violence of his objections' against Newton would prevent readers from fairly judging Goethe's color observations.
—Bruce MacEvoy, Handprint.com, 2008
Influence on the arts
Goethe was initially induced to occupy himself with the study of colour by the questions of hue in painting. "During his first journey to Italy (1786-88), he noticed that artists were able to enunciate rules for virtually all the elements of painting and drawing except color and coloring. In the years 1786—88, Goethe began investigating whether one could ascertain rules to govern the artistic use of color."
This aim came to some fulfillment when several pictorial artists, above all Philipp Otto Runge, took an interest in his colour studies. After being translated into English by Charles Eastlake in 1840, the theory became widely adopted by the art world – especially among the Pre-Raphaelites. J. M. W. Turner studied it comprehensively and referenced it in the titles of several paintings. Wassily Kandinsky considered it "one of the most important works."
Influence on Latin American flags
During a party in Weimar in the winter of 1785, Goethe had a late-night conversation on his theory of primary colours with the South American revolutionary Francisco de Miranda. This conversation inspired Miranda, as he later recounted, in his designing the yellow, blue and red flag of Gran Colombia, from which the present national flags of Colombia, Venezuela and Ecuador are derived.
Influence on philosophers
In the nineteenth century Goethe's Theory was taken up by Schopenhauer in On Vision and Colors, who developed it into a kind of arithmetical physiology of the action of the retina, much in keeping with his own representative realism. In the twentieth century the theory was transmitted to philosophy via Wittgenstein, who devoted a series of remarks to the subject at the end of his life. These remarks are collected as _Remarks on Colour_, (Wittgenstein, 1977). Wittgenstein was interested in the fact that some propositions about colour are apparently neither empirical nor exactly a priori, but something in between: phenomenology, according to Goethe. However, he took the line that 'There is no such thing as phenomenology, though there _are_ phenomenological problems.' He was content to regard Goethe's observations as a kind of logic or geometry. Wittgenstein took his examples from the Runge letter included in the "Farbenlehre", e.g. "White is the lightest colour", "There cannot be a transparent white", "There cannot be a reddish green", and so on. The logical status of these propositions in Wittgenstein's investigation, including their relation to physics, was discussed in Jonathan Westphal's _Colour: a Philosophical Introduction_ (Westphal, 1991).
Reception by scientists
As early as 1853, in Hermann von Helmholtz's lecture on Goethe's scientific works—he says of Goethe's work that he depicts the perceived phenomena — "circumstantially, rigorously true to nature, and vividly, puts them in an order that is pleasant to survey, and proves himself here, as everywhere in the realm of the factual, to be the great master of exposition" (Helmholtz 1892). Helmholtz ultimately rejects Goethe's theory as the work of a poet, but expresses his perplexity at how they can be in such agreement about the facts of the matter, but in violent contradiction about their meaning — 'And I for one do not know how anyone, regardless of what his views about colours are, can deny that the theory in itself is fully consequent, that its assumptions, once granted, explain the facts treated completely and indeed simply'. (Helmholtz 1892)
Although the accuracy of Goethe's observations does not admit a great deal of criticism, his theory's failure to demonstrate significant predictive validity eventually rendered it scientifically irrelevant. Thomas Johann Seebeck was the only prominent scientist among Goethe's contemporaries who acknowledged the theory, but later also saw it critically.
Goethe's colour theory has in many ways borne fruit in art, physiology and aesthetics. But victory, and hence influence on the research of the following century, has been Newton's.
— Werner Heisenberg, 1952
Much controversy stems from two different ways of investigating light and colour. Goethe was not interested in Newton's analytic treatment of colour – but he presented an excellent rational description of the phenomenon of human colour perception. It is as such a collection of colour observations that we must view this book.
Most of Goethe's explanations of color have been thoroughly demolished, but no criticism has been leveled at his reports of the facts to be observed; nor should any be. This book can lead the reader through a demonstration course not only in subjectively produced colors (after images, light and dark adaptation, irradiation, colored shadows, and pressure phosphenes), but also in physical phenomena detectable qualitatively by observation of color (absorption, scattering, refraction, diffraction, polarization, and interference). A reader who attempts to follow the logic of Goethe's explanations and who attempts to compare them with the currently accepted views might, even with the advantage of 1970 sophistication, become convinced that Goethe's theory, or at least a part of it, has been dismissed too quickly.
—Judd, 1970
Mitchell Feigenbaum came to believe that "Goethe had been right about colour!"
As Feigenbaum understood them, Goethe's ideas had true science in them. They were hard and empirical. Over and over again, Goethe emphasized the repeatability of his experiments. It was the perception of colour, to Goethe, that was universal and objective. What scientific evidence was there for a definable real-world quality of redness independent of our perception? — James Gleick, Chaos
Current status
Goethe started out by accepting Newton's physical theory. He soon abandoned it... finding modification to be more in keeping with his own insights. One beneficial consequence of this was that he developed an awareness of the importance of the physiological aspect of colour perception, and was therefore able to demonstrate that Newton's theory of light and colours is too simplistic; that there is more to colour than variable refrangibility.
—Michael Duck, 1988
As a catalogue of observations, Goethe's experiments are useful data for understanding the complexities of human colour perception. Whereas Newton sought to develop a mathematical model for the behaviour of light, Goethe focused on exploring how colour is perceived in a wide array of conditions. Developments in understanding how the brain interprets colours, such as colour constancy and Edwin H. Land's retinex theory bear striking similarities to Goethe's theory (Ribe & Steinle, 2002).
A modern treatment of the book is given by Dennis L. Sepper in the book, Goethe contra Newton: Polemics and the Project for a New Science of Color (Cambridge University Press, 2003).
Munsell color system
In colorimetry, the Munsell color system is a color space that specifies colors based on three color dimensions: hue, value (lightness), and chroma (color purity). It was created by Professor Albert H. Munsell in the first decade of the 20th century and adopted by the USDA as the official color system for soil research in the 1930s.Several earlier color order systems had placed colors into a three-dimensional color solid of one form or another, but Munsell was the first to separate hue, value, and chroma into perceptually uniform and independent dimensions, and was the first to systematically illustrate the colors in three-dimensional space. Munsell’s system, particularly the later renotations, is based on rigorous measurements of human subjects’ visual responses to color, putting it on a firm experimental scientific basis. Because of this basis in human visual perception, Munsell’s system has outlasted its contemporary color models, and though it has been superseded for some uses by models such as CIELAB (L*a*b*) and CIECAM02, it is still in wide use today.
Explanation
The system consists of three independent dimensions which can be represented cylindrically in three dimensions as an irregular color solid: hue, measured by degrees around horizontal circles; chroma, measured radially outward from the neutral (gray) vertical axis; and value, measured vertically from 0 (black) to 10 (white). Munsell determined the spacing of colors along these dimensions by taking measurements of human visual responses. In each dimension, Munsell colors are as close to perceptually uniform as he could make them, which makes the resulting shape quite irregular. As Munsell explains:Desire to fit a chosen contour, such as the pyramid, cone, cylinder or cube, coupled with a lack of proper tests, has led to many distorted statements of color relations, and it becomes evident, when physical measurement of pigment values and chromas is studied, that no regular contour will serve.
—Albert H. Munsell, “A Pigment Color System and Notation”
Hue
Each horizontal circle Munsell divided into five principal hues: Red, Yellow, Green, Blue, and Purple, along with 5 intermediate hues (e.g., YR) halfway between adjacent principal hues. Each of these 10 steps, with the named hue given number 5, is then broken into 10 sub-steps, so that 100 hues are given integer values. In practice, color charts conventionally specify 40 hues, in increments of 2.5, progressing as for example 10R to 2.5YR.
Two colors of equal value and chroma, on opposite sides of a hue circle, are complementary colors, and mix additively to the neutral gray of the same value. The diagram below shows 40 evenly spaced Munsell hues, with complements vertically aligned.
Value
Value, or lightness, varies vertically along the color solid, from black (value 0) at the bottom, to white (value 10) at the top. Neutral grays lie along the vertical axis between black and white.
Several color solids before Munsell’s plotted luminosity from black on the bottom to white on the top, with a gray gradient between them, but these systems neglected to keep perceptual lightness constant across horizontal slices. Instead, they plotted fully saturated yellow (light), and fully saturated blue and purple (dark) along the equator.
Chroma
Chroma, measured radially from the center of each slice, represents the “purity” of a color (related to saturation), with lower chroma being less pure (more washed out, as in pastels). Note that there is no intrinsic upper limit to chroma. Different areas of the color space have different maximal chroma coordinates. For instance light yellow colors have considerably more potential chroma than light purples, due to the nature of the eye and the physics of color stimuli. This led to a wide range of possible chroma levels—up to the high 30s for some hue–value combinations (though it is difficult or impossible to make physical objects in colors of such high chromas, and they cannot be reproduced on current computer displays). Vivid soil colors are in the range of approximately 8.
History and influence
The idea of using a three-dimensional color solid to represent all colors was developed during the 18th and 19th centuries. Several different shapes for such a solid were proposed, including: a double triangular pyramid by Tobias Mayer in 1758, a single triangular pyramid by Johann Heinrich Lambert in 1772, a sphere by Philipp Otto Runge in 1810, a hemisphere by Michel Eugène Chevreul in 1839, a cone by Hermann von Helmholtz in 1860, a tilted cube by William Benson[disambiguation needed] in 1868, and a slanted double cone by August Kirschmann in 1895. These systems became progressively more sophisticated, with Kirschmann’s even recognizing the difference in value between bright colors of different hues. But all of them remained either purely theoretical or encountered practical problems in accommodating all colors. Furthermore, none was based on any rigorous scientific measurement of human vision; before Munsell, the relationship between hue, value, and chroma was not understood.Albert Munsell, an artist and professor of art at the Massachusetts Normal Art School, wanted to create a “rational way to describe color” that would use decimal notation instead of color names (which he felt were “foolish” and “misleading”), which he could use to teach his students about color. He first started work on the system in 1898 and published it in full form in A Color Notation in 1905.
The original embodiment of the system (the 1905 Atlas) had some deficiencies as a physical representation of the theoretical system. These were improved significantly in the 1929 Munsell Book of Color and through an extensive series of experiments carried out by the Optical Society of America in the 1940s resulting in the notations (sample definitions) for the modern Munsell Book of Color. Though several replacements for the Munsell system have been invented, building on Munsell’s foundational ideas—including the Optical Society of America’s Uniform Color Scales, and the International Commission on Illumination’s CIELAB (L*a*b*) and CIECAM02 color models—the Munsell system is still widely used, by, among others, ANSI to define skin and hair colors for forensic pathology, the USGS for matching soil colors, in Prosthodontics during the selection of shades for dental restorations, and breweries for matching beer colors.Sources: a (Theory of Colours),b (Munsell color system)
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