Editing Color theory (section)

== History ==
Color theory is rooted in antiquity, with early musings on color in [[Aristotle]]'s (d. 322 BCE) ''[[On Colors]]'' and [[Claudius Ptolemy]]'s (d. 168 CE) ''[[Optics (Ptolemy)|Optics]]''. The [[Natya_Shastra|Nāṭya Shāstra]] (d. 200 BCE) composed in [[Ancient India]], had an early, functional theory of color,<ref name="Natyashastra">{{cite web |url=https://www.wisdomlib.org/hinduism/book/the-natyashastra/d/doc210153.html |title=Chapter XXIII 'Costumes and Make-up' |last=Shastri |first=Babulal |publisher=Motilal Banarasidass |date=April 16, 2025 |website=Wisdomlib |access-date=April 16, 2025}}</ref> considering four colours as primary, [[black]], [[blue]], [[yellow]] and [[red]]. It also describes the production of derived colors from [[Primary_color|primary colors]].

{{Quote box
 |quote  = The bluish white (kāraṇḍava) colour, is made up of the white and the blue, and the yellowish white colour (pāṇḍu) of the white and the yellow. The lotus (padma) colour is made up of the white and the red, and the green (harit) colour, of the yellow and the blue. The dark red (kāṣāya) colour is made up of the blue and the red, and the pale-red (gaura) colour of the red and the yellow. These are the derivative colours. Besides these there are [many] minor colours which may be made up of three or four [original] colours.
 |author = [[Bharata_(sage)|Bharata]]
 |source = ''[[Natya_Shastra|Nāṭya Shāstra]]'', Chapter XXIII "Costumes and Make-up".
}}

The influence of light on color was investigated and revealed further by [[al-Kindi]] (d. 873) and [[Ibn al-Haytham]] (d. 1039). [[Ibn Sina]] (d. 1037), [[Nasir al-Din al-Tusi]] (d. 1274), and [[Robert Grosseteste]] (d. 1253) discovered that contrary to the teachings of Aristotle, there are multiple color paths to get from black to white.<ref>{{cite journal |last1=Smithson |first1=H.E. |last2=Dinkova-Bruun |first2=G. |last3=Gasper |first3=G.E.M. |last4=Huxtable |first4=M. |last5=McLeish |first5=T.C.B. |last6=Panti |first6=C.P. |title=A three-dimensional color space from the 13th century |journal=J. Opt. Soc. Am. A |date=2012 |volume=29 |issue=2 |pages=A346–A352 |doi=10.1364/josaa.29.00A346|pmid=22330399 |pmc=3287286 |bibcode=2012JOSAA..29A.346S }}</ref><ref>{{cite journal |last1=Kirchner |first1=E. |title=Color theory and color order in medieval Islam: A review |journal=Color Research & Application |date=2013 |volume=40 |issue=1 |pages=5–16 |doi=10.1002/col.21861}}</ref> More modern approaches to color theory principles can be found in the writings of [[Leone Battista Alberti]] (c. 1435) and the notebooks of [[Leonardo da Vinci]] (c. 1490).[[File:Color diagram Charles Hayter.jpg|thumb|Page from 1826 ''A New Practical Treatise on the Three Primitive Colours Assumed as a Perfect System of Rudimentary Information'' by [[Charles Hayter]]]]

[[Isaac Newton]] (d. 1727) worked extensively on color theory, helping and developing his own theory from stating the fact that white light is composed of a spectrum of colors, and that color is not intrinsic to objects, but rather arises from the way an object reflects or absorbs different wavelengths. His 1672 paper on the nature of white light and colours forms the basis for all work that followed on colour and colour vision.<ref>{{Citation |last=Marriott |first=F.H.C. |date=2014 |orig-year=1962 (print) |title=Colour Vision: Introduction |url=https://linkinghub.elsevier.com/retrieve/pii/B9781483230894500212 |work=The Visual Process |publisher=Elsevier |pages=219–229 |doi=10.1016/b978-1-4832-3089-4.50021-2 |isbn=978-1-4832-3089-4 |access-date=2025-03-02 |language=en}}</ref>

The RYB primary colors became the foundation of 18th-century theories of [[color vision]],{{Citation needed|date=September 2018}} as the fundamental sensory qualities that are blended in the perception of all physical colors, and conversely, in the physical mixture of [[pigment]]s or [[dye]]s. These theories were enhanced by 18th-century investigations of a variety of purely psychological color effects, in particular the contrast between "complementary" or opposing hues that are produced by color afterimages and in the contrasting shadows in colored light. These ideas and many personal color observations were summarized in two founding documents in color theory: the ''[[Theory of Colours]]'' (1810) by the German poet [[Johann Wolfgang von Goethe]], and ''The Law of Simultaneous Color Contrast'' (1839) by the French industrial chemist [[Michel Eugène Chevreul]]. [[Charles Hayter]] published ''A New Practical Treatise on the Three Primitive Colours Assumed as a Perfect System of Rudimentary Information'' (London 1826), in which he described how all colors could be obtained from just three.

Subsequently, German and English scientists established in the late 19th century that color perception is best described in terms of a different set of primary colors—red, green and blue-violet ([[RGB color model|RGB]])—modeled through the additive mixture of three monochromatic lights. Subsequent research anchored these primary colors in the differing responses to light by three types of [[Cone cell|color receptors]] or ''cones'' in the [[retina]] ([[trichromacy]]). On this basis the quantitative description of the color mixture or colorimetry developed in the early 20th century, along with a series of increasingly sophisticated models of [[color space]] and color perception, such as the [[opponent process]] theory.

[[File:Munsell-system.svg|thumb|left|[[Munsell color system|Munsell]]'s 1905 color system represents colors using three color-making attributes, ''value'' (lightness), ''chroma'' (saturation), and ''hue''.]]

Across the same period, industrial chemistry radically expanded the color range of lightfast synthetic pigments, allowing for substantially improved saturation in color mixtures of dyes, paints, and inks. It also created the dyes and chemical processes necessary for color photography. As a result, three-color printing became aesthetically and economically feasible in mass printed media, and the artists' color theory was adapted to primary colors most effective in inks or photographic dyes: cyan, magenta, and yellow (CMY). (In printing, dark colors are supplemented by black ink, called "key," to make the [[CMYK]] system; in both printing and photography, white is provided by the color of the paper.) These CMY primary colors were reconciled with the RGB primaries, and subtractive color mixing with additive color mixing, by defining the CMY primaries as substances that ''absorbed'' only one of the retinal primary colors: cyan absorbs only red (−R+G+B), magenta only green (+R−G+B), and yellow only blue-violet (+R+G−B). It is important to add that the CMYK, or process, color printing is meant as an economical way of producing a wide range of colors for printing, but is deficient in reproducing certain colors, notably orange and slightly deficient in reproducing purples. A wider range of colors can be obtained with the addition of other colors to the printing process, such as in [[Pantone]]'s [[Hexachrome]] printing ink system (six colors), among others.

For much of the 19th century artistic color theory either lagged behind scientific understanding or was augmented by science books written for the lay public, in particular ''Modern Chromatics'' (1879) by the American physicist [[Ogden Rood]], and early color atlases developed by [[Albert Munsell]] (''Munsell Book of Color'', 1915, see [[Munsell color system]]) and [[Wilhelm Ostwald]] (Color Atlas, 1919). Major advances were made in the early 20th century by artists teaching or associated with the German [[Bauhaus]], in particular [[Wassily Kandinsky]], [[Johannes Itten]], [[Faber Birren]] and [[Josef Albers]], whose writings mix speculation with an empirical or demonstration-based study of color design principles.