Editing Complementary colors (section)

==In theory and art==
===In color theory===
The effect that colors have upon each other had been noted since antiquity. In his essay ''[[On Colors]]'', [[Aristotle]] observed that "when light falls upon another color, then, as a result of this new combination, it takes on another nuance of color".<ref>[[On Colors]] or ''De Coloribus'' (793b) cited in John Gage, ''Couleur et Culture'', pg. 13</ref> Saint [[Thomas Aquinas]] had written that purple looked different next to white than it did next to black, and that gold looked more striking against blue than it did against white; the Italian Renaissance architect and writer [[Leon Battista Alberti]] observed that there was harmony (''coniugatio'' in Latin, and ''amicizia'' in Italian) between certain colors, such as red–green and red–blue; and [[Leonardo da Vinci]] observed that the finest harmonies were those between colors exactly opposed (''retto contrario''), but no one had a convincing scientific explanation why that was so until the 18th century.

In 1704, in his treatise on optics, [[Isaac Newton]] devised a circle showing a [[spectrum]] of seven colors. In this work and in an earlier work in 1672, he observed that certain colors around the circle were opposed to each other and provided the greatest contrast; he named red and blue (modern cyan),<ref>{{Cite journal |last=McLaren |first=K. |date=December 1985 |title=Newton's indigo |url=https://onlinelibrary.wiley.com/doi/10.1002/col.5080100411 |journal=Color Research & Application |language=en |volume=10 |issue=4 |pages=225–229 |doi=10.1002/col.5080100411 |issn=0361-2317 |archive-date=February 1, 2024 |access-date=February 1, 2024 |archive-url=https://web.archive.org/web/20240201043545/https://onlinelibrary.wiley.com/doi/10.1002/col.5080100411 |url-status=live }}</ref> yellow and violet, and green and "a purple close to scarlet".<ref>John Gage, ''Couleur et culture'', pg. 172.</ref>

In the following decades, scientists{{who|date=May 2022}} refined Newton's color circle, eventually giving it twelve colors: the three primary colors (yellow, blue, and red); three secondary colors (green, purple and orange), made by combining primary colors; and six additional tertiary colors, made by combining the primary and secondary colors.{{citation needed|date=May 2022}}

In two reports read before the Royal Society (London) in 1794, the American-born British scientist [[Benjamin Thompson]], Count Rumford (1753–1814), coined the term ''complement'' to describe two colors that, when mixed, produce white. While conducting photometric experiments on factory lighting in Munich, Thompson noticed that an "imaginary" blue color was produced in the shadow of yellow candlelight illuminated by skylight, an effect that he reproduced in other colors by means of tinted glasses and pigmented surfaces. He theorized that "To every color, without exception, whatever may be its hue or shade, or however it may be compounded, there is another in perfect harmony to it, which is its complement, and may be said to be its companion." He also suggested some possible practical uses of this discovery. "By experiments of this kind, which might easily be made, ladies may choose ribbons for their gowns, or those who furnish rooms may arrange their colors upon principles of the most perfect harmony and of the purest taste. The advantages that painters might derive from a knowledge of these principles of the harmony of colors are too obvious to require illustration."<ref>[https://books.google.com/books?id=udu4AAAAIAAJ&dq=%22count+rumford%22+experiments+coloured+shadows&pg=PA51 Benjamin Thompson, Count Rumford, ''Conjectures respecting the Principle of the Harmony of Colors'', ''The Complete Works of Count Rumford''], Volume 5, pp. 67–68. (Google Books).</ref>

In the early 19th century, scientists and philosophers across Europe began studying the nature and interaction of colors. The German poet [[Johann Wolfgang von Goethe]] presented his own theory in 1810, stating that the two primary colors were those in the greatest opposition to each other, yellow and blue, representing light and darkness. He wrote that "Yellow is a light which has been dampened by darkness; blue is a darkness weakened by light."<ref>Goethe (1810), ''Theory of Colors'', paragraph 502.</ref> Out of the opposition of blue and yellow, through a process called "steigerung", or "augmentation" a third color, red, was born.{{page needed|date=June 2013}} Goethe also proposed several sets of complementary colors which "demanded" each other. According to Goethe, "yellow 'demands' violet; orange [demands] blue; [[Theory of Colours#Goethe's colour wheel|purple]] [demands] green; and vice versa".<ref>Goethe, ''Theory of Colours'', trans. Charles Lock Eastlake, Cambridge, MA: MIT Press, 1982. {{ISBN|0-262-57021-1}}</ref> Goethe's ideas were highly personal and often disagreed with other scientific research, but they were highly popular and influenced some important artists, including [[J. M. W. Turner]].<ref>John Gage, ''Couleur et Culture'', pp. 201–203.</ref>

At about the same time that Goethe was publishing his theory, a British physicist, doctor and Egyptologist, [[Thomas Young (scientist)|Thomas Young]] (1773–1829), showed by experiments that it was not necessary to use all the colors of spectrum to create white light; it could be done by combining the light of just three colors; red, green, and blue. This discovery was the foundation of [[additive color]]s, and of the [[RGB color model]].<ref>Isabelle Roelofs and Fabien Petillion, La couleur expliqée aux artistes, p. 14.</ref> He showed that it was possible to create magenta by combining red and blue light; to create yellow by mixing red and green light; and to create cyan, or [[blue-green]], by mixing green and blue. He also found that it was possible to create virtually any other color by modifying the intensity of these colors. This discovery led to the system used today to create colors on a computer or television display. Young was also the first to propose that the [[retina]] of the eye contained nerve fibers which were sensitive to three different colors. This foreshadowed the modern understanding of [[color vision]], in particular the finding that the eye does indeed have three color receptors which are sensitive to different wavelength ranges.<ref>{{cite journal|author= Young, T.|year= 1802|title= Bakerian Lecture: On the Theory of Light and Colours|journal= Phil. Trans. R. Soc. Lond.|volume= 92|pages=12–48| doi= 10.1098/rstl.1802.0004|doi-access= free}}</ref>

At about the same time as Young discovered additive colors, another British scientist, [[David Brewster]] (1781–1868), the inventor of the [[kaleidoscope]], proposed a competing theory that the true primary colors were red, yellow, and blue, and that the true complementary pairs were red–green, blue–orange, and yellow–purple. Then a German scientist, [[Hermann von Helmholtz]], (1821–1894), resolved the debate by showing that colors formed by light, additive colors, and those formed by pigments, subtractive colors, did in fact operate by different rules, and had different primary and complementary colors.<ref>Isabelle Roelofs and Fabien Petillion, ''La couleur expliquée aux artistes'', p. 18.</ref>

Other scientists looked more closely at the use of complementary colors. In 1828, the French chemist [[Eugene Chevreul]], making a study of the manufacture of [[Gobelin]] tapestries to make the colors brighter, demonstrated scientifically that "the arrangement of complementary colors is superior to any other harmony of contrasts". His 1839 book on the subject, ''De la loi du contraste simultané des couleurs et de l'assortiment des objets colorés'', showing how complementary colors can be used in everything from textiles to gardens, was widely read in Germany, France and England, and made complementary colors a popular concept. The use of complementary colors was further publicized by the French art critic [[Charles Blanc]] in his book ''Grammaire des arts et du dessin'' (1867) and later by the American color theorist [[Ogden Rood]] in his book ''Modern Chromatics'' (1879). These books were read with great enthusiasm by contemporary painters, particularly [[Georges Seurat]] and [[Vincent van Gogh]], who put the theories into practice in their paintings.<ref>John Gage, ''Couleur et culture'', pp. 174–75</ref>

In 2022 a team from Los Alamos National Laboratory found that three dimensional perceptual color space is not [[Riemannian geometry|Riemannian]], as has been widely accepted since being proposed by Riemann and furthered by Helmholtz and [[Erwin Schrödinger|Schroedinger]]. They conducted comparative tests with human subjects using 'two-alternative forced choice' tasks for greater accuracy. They found large color differences were perceived as less distant than the sum of all distances within them. When these perceived distances are plotted it results in a [[Non-Euclidean geometry|non-Euclidean]] color space. This finding most strongly impacts [[Analogous colors|analogous color pairings]], as the distance between colors grows larger as you zoom in on an area of color space. They conclude there would need to be changes to the color standard used by the [[General Conference on Weights and Measures#CIPM|International Commission of Weights and Measures]], to account for diminishing perceptual returns on color spacings.<ref>{{Cite journal |last1=Bujack |first1=Roxana |last2=Teti |first2=Emily |last3=Miller |first3=Jonah |last4=Caffrey |first4=Elektra |last5=Turton |first5=Terece L. |date=2022-05-03 |title=The non-Riemannian nature of perceptual color space |journal=Proceedings of the National Academy of Sciences |language=en |volume=119 |issue=18 |pages=e2119753119 |doi=10.1073/pnas.2119753119 |doi-access=free |issn=0027-8424 |pmc=9170152 |pmid=35486695|bibcode=2022PNAS..11919753B }}</ref>

<gallery>
File:Newton's color circle.png|Newton's color circle (1704) displayed seven colors. He declared that colors opposite each other had the strongest contrast and harmony.
File:Boutet 1708 color circles.jpg|A Boutet color circle from 1708 showed the traditional complementary colors; red and green, yellow and purple, and blue and orange.
File:GoetheFarbkreis.jpg|The color wheel designed by [[Johann Wolfgang von Goethe]] (1810) was based on the idea that the primary colors yellow and blue, representing light and darkness, were in opposition to each other.
</gallery>

===In art===
In 1872, [[Claude Monet]] painted ''[[Impression, Sunrise]]'', a tiny orange sun and some orange light reflected on the clouds and water in the center of a hazy blue landscape. This painting, with its striking use of the complementary colors orange and blue, gave its name to the [[impressionist]] movement. Monet was familiar with the science of complementary colors, and used them with enthusiasm. He wrote in 1888, "color makes its impact from contrasts rather than from its inherent qualities....the primary colors seem more brilliant when they are in contrast with their complementary colors".<ref>Philip Ball, Histoire vivante des couleurs, p. 260.</ref>

Orange and blue became an important combination for all the impressionist painters. They all had studied the recent books on color theory, and they knew that orange placed next to blue made both colors much brighter. [[Auguste Renoir]] painted boats with stripes of chrome orange paint straight from the tube. [[Paul Cézanne]] used orange made of touches of yellow, red and ochre against a blue background.

[[Vincent van Gogh]] was especially known for using this technique; he created his own oranges with mixtures of yellow, ochre and red, and placed them next to slashes of sienna red and bottle-green, and below a sky of turbulent blue and violet. He also put an orange moon and stars in a cobalt blue sky. He wrote to his brother Theo of "searching for oppositions of blue with orange, of red with green, of yellow with purple, searching for broken colors and neutral colors to harmonize the brutality of extremes, trying to make the colors intense, and not a harmony of greys".<ref>Vincent van Gogh, ''Lettres à Theo'', p. 184.</ref>

Describing his painting, ''[[The Night Café]]'', to his brother Theo in 1888, Van Gogh wrote: "I sought to express with red and green the terrible human passions. The hall is blood-red and pale yellow, with a green billiard table in the center, and four lamps of lemon yellow, with rays of orange and green. Everywhere it is a battle and antithesis of the most different reds and greens."<ref>Vincent van Gogh, ''Corréspondénce general'', number 533, cited by John Gage, ''Practice and Meaning from Antiquity to Abstraction''.</ref>

<gallery>
File:Claude Monet, Impression, soleil levant.jpg|''[[Impression, Sunrise]]'' by [[Claude Monet]] (1872) featured a tiny but vivid orange sun against a blue background. The painting gave its name to the Impressionist movement.
File:Renoir12.jpg|''[[Oarsmen at Chatou]]'' by [[Pierre-Auguste Renoir]] (1879). Renoir knew that orange and blue brightened each other when put side by side.
File:SelbstPortrait VG2.jpg|In this self-portrait (1889), [[Vincent van Gogh]] made the most of the contrast between the orange of his hair and the blue background.
File:VanGogh-starry night ballance1.jpg|''[[The Starry Night|Starry Night]]'' by Vincent van Gogh (1889) features yellow stars and a yellow moon.
File:Vincent Willem van Gogh 076.jpg|''The Night Café'' by Vincent van Gogh (1888) used red and green to express what van Gogh called "the terrible human passions".
</gallery>