Color theory (Goethe)
The theory of colors, which can be traced back to Johann Wolfgang von Goethe , is contained in his work on the theory of colors . In it he presented the reflections, literature studies and attempts he had made over many years about the nature of color . Goethe did not want to judge and explain the phenomenon of color from a one-sided physical point of view, or merely from an aesthetic or practical point of view, but rather to grasp and describe it as a whole. However, he only achieved recognition with the section "Physiological colors", which contains the knowledge about color perception . He was wrong, especially in the section "Physical colors," the refutation of him as the predominantly from Isaac Newton derived science was meant findings. Goethe himself valued the results of his research on color higher than those of his entire literary output. Even in old age he said to Johann Peter Eckermann : “I do not imagine anything that I have achieved as a poet. […] But that in my century in the difficult science of color theory I am the only one who knows what is right, I do something to help myself […]. "
The work
on the left: dark stripe on a light background,
right: light stripe on a dark background
In the narrower sense, Goethe's theory of colors is understood as the three-part text that Goethe published in 1810 under the heading of the theory of colors . It consists of a "didactic part", a "polemical part" and a "historical part". In addition, a volume with tables was published in 1810. In a broad sense, Goethe's theory of colors means all of Goethe's writings on his color research. Understood in this way, the work also consists of these individual works:
-
Contributions to chromatics
- Try to discover the elements of color theory
- From the colored shadows
- Attempt as a mediator between object and subject
- Experience and science
- Additions to the theory of colors. Entoptic colors .
Throughout his life, Goethe strove intensely for the dissemination and scientific recognition of this most extensive of his works, for example through Georg Christoph Lichtenberg , who of course did not agree with his theses. But while Goethe's color theory was well received by artists such as Philipp Otto Runge and William Turner , his views against Isaac Newton's theory of light, which was a hundred years older, could not prevail in natural science. Newton had experimentally proven that white light is composed of colored lights, on the other hand Goethe tried to show that white light is not composed and that colors result from an interaction of light and darkness. In this sense, he interpreted the edge spectra that he saw when looking at dark stripes on a light background and light stripes on a dark background through a prism . This experience gave him the decisive impetus to develop his own color theory.
The theory of colors is still significant in terms of intellectual history and the history of science because it documents Goethe's holistic approach to the observation of nature and his ability to observe. It proves his preference for intuition over abstraction. From this point of view and subjective perception, he also derived the psychological effects of colors on people and thus developed a kind of color psychology .
Goethe took an active part in many scientific discoveries of his time and was in contact with many researchers of his time by letter or personally. The influence of Johann Gottfried Herder is significant for Goethe's scientific interest .
The first edition of Zur Farbenlehre appeared on May 16, 1810 in an edition of 500 copies on white and 250 copies on gray paper in the Cotta'sche publishing house . In the same year the mathematician, physicist and astronomer Carl Brandan Mollweide refuted in the text Examination of the theory of colors of Mr. Goethe and defense of Newton's system against it , which appeared in Halle (Saale) , Goethe's view on the origin of colors.
On the history of science background
Even in ancient times was Refraction an issue as their understanding of the correct positioning of stars in astronomy was important. Johannes Kepler, with his writing Paralipomena ad Vitellionem from 1604, can be regarded as the founder of modern optics . Already before 1600 there were various attempts to explain the origin of the colors of the rainbow by refraction - for example by Roger Bacon and Dietrich von Freiberg . However, an exact formulation was only possible with the law of refraction , which was correctly formulated by Willebrord van Roijen Snell and René Descartes .
Up to the 17th century, essentially three different, contradicting models existed to explain sight and light. They were used alternately depending on the phenomenon that was to be explained:
- Visual rays emitted by the eye scan the objects in the environment, similar to a white cane or a modern radar . This view was widespread in ancient times. It was refuted around 1000 AD by the Arab scholar Alhazen . However, his findings were only later disseminated in the West through the mediation of Kepler and Witelo . The derivation of the principles of perspective in the Renaissance took place partly on the model of the visual rays.
- Light ether as an infinite and fluid medium is necessary to explain the wave properties of light, which show up in diffraction phenomena, as in the Huygens principle . The idea that images are constantly beingdetachedfrom thingsand that things are reproduced in the eye was already present in antiquity.
- The corpuscle theory of light assumes that a lot of very fast particles are emitted by a light source, comparable to cannon balls. With this model Newton provided an explanation of the splitting of light in the prism, as in the rainbow, by means of dispersion .
In Newton's time in the 17th and 18th centuries there were controversial discussions about whether light had a corpuscular or wave-like character. The riddle of the surplus arcs in the rainbow prompted Thomas Young to carry out his famous double slit experiment in 1801 . In doing so, he demonstrated the wave nature of light and, in return, was able to reveal the secret in 1804 by looking at interference phenomena .
1800 dated as the year of the discovery of the infrared by William Herschel , which was demonstrably also observed by Goethe. In 1801, the ultraviolet radiation followed by Johann Wilhelm Ritter , with whom Goethe had begun to cooperate scientifically in the autumn of 1800. Because Ritter went to see Goethe one day after his discovery and experimented with him two days later, there is every reason to believe that Goethe was one of the first to hear of Ritter’s discovery.
In accordance with his understanding of the “unity of nature”, Goethe not only asked physical questions, for example about the nature of light, but also asked how it, especially its color, is perceived . The latter is not a purely physical issue. Goethe did not come into contradiction to physical science because he went beyond its question, but because he considered its answers to be wrong and replaced it with his own wrong physical conclusions. The occasion was his view through a prism, from which he mistakenly expected the same results as Newton from his prism experiment. Because that was not the case, he negligently concluded "that the Newtonian teaching was wrong."
The prism experiment
Newton had guided a narrow beam of light falling through a hole through a prism and thereby made the colored lights contained in the white light - the spectral colors - visible separately; In this famous experiment, the colors blue, turquoise, green, yellow, red (with many fine intermediate levels) appear.
Goethe himself gave a description of how he carried out his very first experiment to split light through a prism:
“I was just in a completely whitewashed room; When I took the prism in front of my eyes, bearing in mind Newtonian theory, I expected the whole white wall to be colored in different stages, to see the light returning from there into the eye splintered into so many colored lights.
But how surprised I was when the white wall looked at through the prism remained white, that only where a dark touched it showed a more or less decided color, that in the end the window bars appeared most vividly colored, but light gray There was no trace of color in the sky outside. It didn't take much thought, so I realized that a limit was necessary in order to produce colors, and as if by instinct I immediately said out loud to myself that Newton's teaching was wrong. "
Its white wall was an extended source of light. Each individual ray of light is broken down into a bundle of colored rays as it passes through the prism. But each of these colored individual rays is superimposed by individual rays of all other colors, which originate from the neighboring incoming rays. In total, white rays leave the prism again, except when no neighboring white rays enter. Then more or less of the other partial beams are missing from the superposition, and a colored impression is created. Goethe's spectra were created where the incoming neighboring rays were absent or very weak, for example at the edges of the window bars. They formed a half-gap and produced an edge spectrum. Newton made his experiment more consistent by not only using a whole slit, but even a hole, thus holding back the disturbing neighboring rays all around. Goethe mocked the fact that it had to be dark around the experimental setup in his laboratory with the following lines:
"Friends, flee the dark chamber,
where the light is confused ..."
Although Goethe himself carried out countless physical experiments in the specially set up darkroom in his house on Frauenplan in Weimar, he did not limit himself to this experimental arrangement with little light and a lot of darkness. Just as important to him were experiments with opposite lighting conditions, i.e. with a lot of light and little darkness. The most important of these experiments is the exact reverse of Newton's famous experiment; Goethe placed his prism in full sunlight and stuck a black cardboard circle in the middle that was the same size as the Newtonian hole. Goethe's surprising observation has often been reproduced: Again a colored spectrum results, but with the complementary colors of the Newtonian spectrum: yellow (instead of Newton's blue), red (instead of Newton's turquoise), purple-magenta (instead of Newton's green), blue (instead of Newton's yellow), turquoise (instead of Newton's red). Because Goethe found both experiments to be completely equal, he refused to only experiment in the dark. Goethe assumed a duality of light and darkness, so saw both as equal (polar) factors for the development of color.
Reception of natural scientists
During Goethe's lifetime (between 1810 and 1832) countless natural scientists and mathematicians commented on Goethe's Newton criticism in the theory of colors , in reviews, books, book chapters, footnotes, and open letters. Most of these votes (almost half) were against Goethe, especially Thomas Young , Louis Malus , Pierre Prévost and Gustav Theodor Fechner . A third of the statements from the natural sciences were in favor of Goethe, especially Thomas Johann Seebeck , Johann Salomo Christoph Schweigger and Johann Friedrich Christian Werneburg - the latter tried to mathematically support the theory - and a fifth were ambivalent or undecided.
Hermann von Helmholtz , who held Goethe in high esteem not only as a poet but also because of his other scientific work, considered the main thesis of the theory of colors to be simply wrong. At the same time he saw what prompted Goethe to focus on this thesis: “White, which appears to the eye as the simplest, purest of all color impressions, should be composed of the impure manifold. Here the poet seems to have felt with a quick premonition that the consequences of this sentence put his whole principle into question, and that is why this assumption seems so unthinkable, so namelessly absurd. We must regard his theory of colors as an attempt to save the immediate truth of the sensual impression from the attacks of science. Hence the zeal with which he strives to train and defend it, the passionate irritation with which he attacks his opponent, the predominant importance which he ascribes to it over all his other works, and the impossibility of conviction and reconciliation. "
Heisenberg wrote in 1941 that the division of the world into an objective reality that can be explored by natural science and a subjective reality that is accessible to our original world experience is not tenable from the point of view of modern physics. Newton and Goethe proceeded from different layers of reality, the use of his measurement technology provides Newton with an intersubjective comparability of the test data, Goethe's color studies are only subjectively real in contrast to the objective reality of Newton's studies. Friedrich Steinle emphasizes that, despite different experimental methods, both paradigmatically stand for different experimental work, but both clearly within the system of modern natural science. Michael Faraday and David Brewster proceeded similarly to Goethe .
In a dissertation in 2015, a property of spectral phenomena discovered by Goethe, the “complementarity of optical spectra”, was experimentally investigated. The experiments represent symmetrized generalizations of Newton's experiments. They show that under very general conditions it is not possible to generate a slit spectrum without simultaneously creating the conditions for the creation of the complementary spectrum. Spectra that are complementary to one another turn out to be partial phenomena of an experimental context.
Preparatory work for color theory
Goethe's intensive preoccupation with the subject of color began in 1777 at the latest, when he noticed colored shadows in the evening sun on the snow on the Brocken . Around 1790, when looking through a prism, he saw edge spectra ( see prism experiment ), the established scientific interpretation of which he countered with his own view of the nature of colored light under the title Contributions to Chromatics . It stands at the beginning of the paper On Theory of Colors, which was published in 1810 and expanded in 1820 , but was published in advance in 1791/95 under the title Contributions to Optics .
A quote on his trip to the Harz Mountains (November 29 to December 16, 1777) opens up the emotional basis for Goethe's interest in colors.
“On a trip to the Harz Mountains in winter, I climbed down from the Brocken in the evening, the wide areas up and down were covered with snow, the heather covered with snow, all the scattered trees and protruding cliffs, all the trees and rocks completely covered with frost, the sun set down against the Oderteiche.
If during the day, with the yellowish tone of the snow, faint violet shadows were noticeable, they now had to be addressed as deep blue when an intensified yellow shone from the illuminated parts. But when the sun finally approached its setting and its ray, which was extremely moderate due to the stronger fumes, covered the whole world around me with the most beautiful purple color, then the shadow color changed into a green, which in its clarity a sea green, in its beauty one Emerald green could be compared.
The appearance became more and more lively, one believed to be in a fairy world, because everything was dressed in the two lively and so beautifully matching colors, until finally, with the sunset, the magnificent appearance turned into a gray twilight and gradually into a lunar and lost starry night. "
Such observations can also be found on the trip to Italy. Here he was probably occupied with the coloring in painting during his trip to Italy (1786–1788) out of artistic interest. He did watercolors himself and studied Italian landscape painting. One of the theoretical writings he studied was the treatise De radiis visus et lucis in vitris, perspectivis et iride by Marco Antonio de Dominis .
The first scientific preparatory work for the later theory of colors are the contributions to chromatics , which initially appeared in 1791 and 1792 as contributions to optics in the publishing house of the Industrie-Comptoir Weimar and then found their way into the theory of colors in the narrower sense.
In an attempt to discover the elements of color theory , a manuscript from 1794, Goethe investigates the “difficulty of explaining and uniting what is meant by white [2, 90]. ... Newton says that the white and all gray colors between white and black can be composed of colors. ”( 2, 87 ) The problem of the origin of white also later represented the key to understanding colors for Goethe, and he leads a series of facts.
“But we still have to pay attention to one strange circumstance. As soon as we mix all the colors of the scheme together in a certain proportion, the result is a non-color ... which, when painted on white paper, gives us completely the concept of gray (2, 83) "... and contradicts Newton:" I may say boldly: If you think of experiments of whatever kind you want, you will never be able to put together a white pigment from colored pigments that does not appear gray or brownish next to or on completely pure snow or powder. "
This dispute was based on the different assumptions of both. While Newton investigated the additive color synthesis of light , Goethe dealt with the subtractive color synthesis of colorants . The essay From the colored shadows , another preliminary work on the theory of colors , probably dates from 1792.
As a methodical and programmatic preparatory work in the broader sense, the essay Attempt as a Mediator of Object and Subject , which was only available in print in 1823, can be considered. Although Goethe described himself as a bad mathematician, his approach has the methodological rigor of mathematics.
Goethe exchanged verbally and in letters with Friedrich Schiller about the theory of colors, and his physiological knowledge was helpful to him. Together they worked out the temperament rose. Goethe took Schiller's riddle "We come from, our six siblings" as a motto in On Theory of Colors .
Goethe's theory of colors in the narrower sense
The main work of Goethe's color theory is the font that Goethe called Zur Farbenlehre and published in 1810. The work consists essentially of three main parts: a didactic, which presents its own findings, a polemical, which turns against Newton's theory of color, and a historical, which recapitulates the various historical theories on color and light.
All of the following quotations from Ott, Proskauer, 1992 are given in this article in the form (- volume, page). The book contains 15 tables, some in color, to aid understanding of the text (2, 231–276).
I. Didactic part
Goethe first differentiates between three types of color and color effect.
- Physiological colors
Physiological colors are after Goethe
"Noticed as a fleeting effect and counteraction of the eye itself."
He continues:
"These colors , which make the foundation of the whole teaching ... have so far ... been viewed as a delusion and ailment."
First, sham colors , eye illusions, facial deception, and pathological colors (1, 64) are discussed.
- Physical colors
Goethe understands physical colors
"As a temporary effect of colorless, translucent, transparent, opaque bodies on light."
He initiates the physical color department as follows
"Such colors are therefore produced in our eyes by such external, specific occasions."
and explains his term "the cloudy" - as an infinite number of shades of gray on the black and white scale .
A large number of experiments are described that can be carried out with parchment paper , opal glass , concave and convex lenses , prisms - some with water filling, black panes, various single-colored squares and also openings in the shutter and soap bubbles with reflected or transmitted light.
- Chemical colors
Body colors prevail according to Goethe,
"Where we can confidently address them as permanent, as really indwelling to the bodies."
II. Polemical part
Even when the work was published, there was a conflicting dispute in contemporary experts about the views of Goethe and Newton. For Newton, white light consists of individual components that are characterized by the spectral colors . But Newton also said: “ The rays are not colored. “For Goethe's striving for unity of the world, light is also a unity, colors as a property of light can only be the result of the mixture of brightness and darkness.
So the fundamental question was: Is light a compound phenomenon according to Newton and different qualities lead to color or is light a "unit", as Goethe put it, and color is a phenomenon of different qualities.
Goethe contrasts his own color theory with Newton's color theory in the chapter Unveiling Newton's Theory (3, 208/209):
| Property of white sunlight | Newton | Goethe |
|---|---|---|
| homogeneity | Light is composed ( heterogeneous ). | Light is a unit ( homogeneous ). |
| spectrum | White light is composed of colored lights . | White light is the primary one. The light cannot be composed of darkness . |
| Interaction with matter | The light is decomposed by refraction , inflection and reflection . | Refraction, inflexion and reflection can exist without color phenomena. |
| analysis | [White light] is broken down into seven [pure] , rather into innumerable colors . | There are only two pure colors, blue and yellow. The rest are degrees of these colors or impure. |
| synthesis | As it has been decomposed [the white light], it can be reassembled. | Neither can colorless light be composed of apparent [visible] colors, nor can white light be composed of colored pigments. |
III. Historical part
Goethe intensively studied and partially commented on the literature on color theory that was available to the learned world at the time. In addition, he researched the work of great natural scientists (Galileo, Kepler, Descartes ...) on the topic and sometimes even dared to make statements about the human character of the respective scientist.
It was common, if a work saw itself as fundamental, to refer to the views of the previous authorities - often starting in antiquity. On the one hand, the author proved himself to be an expert in his field and, on the other hand, enabled him to support his views through the authority of recognized researchers.
René Descartes ' color theory of light spheres occupied Goethe. A description of light as indivisible particles is also used in modern physics ( photon ) in addition to the description of waves, but this particle character has only been observable since the end of the 19th century. Athanasius Kircher's , Nikolaus Malebranches and Robert Boyle's works are discussed. Markus Marci's work on the rainbow testifies to Goethe
“Of the seriousness, diligence and perseverance of the author; [but it was] somewhat sad on the whole. "
Hooke's work helped Goethe in the experimental but not in the theoretical field (4, 251). The experimental evaluation in Johann Christoph Sturm's color theory cannot stand before Goethe.
Goethe discusses the writings on the theory of colors by Thomas Sprat , Edme Mariotte , Voltaire , Tobias Mayer , Johann Heinrich Lambert , Benjamin Franklin , Joseph Priestley , Jean-Paul Marat , Anton Raphael Mengs , Christian Westfeld and Robert Blair . Finally, the defense of Newton's color theory by the physics professor Johann Theophilus Desaguliers (5, 356 - 362) and the eulogy of Bernard le Bovier de Fontenelles (5, 386 - 392) on Newton are discussed.
Additions to the theory of colors. Entoptic colors
This work dates from 1820 . Goethe devised sophisticated experimental arrangements and observed
“[...] through the extremely interesting Seebeck double spar prism [the entoptic colors] in the double refraction of sunlight. These colors were called entoptic because they can be seen within certain bodies. "
The simplest experiment on this double refraction was, to put it succinctly, prepared as follows:
“You cut a moderately thick mirror pane into several one and a half inch squares, they glow through and cool quickly. What does not burst during this treatment is now able to produce entoptic colors. "
The entire experimental set-up is outlined on page (2, 217).
“The external basic condition [is] a pure, cloudless, blue atmosphere [...]. To St. John at noon is the brightest moment. At the culmination of the sun a white cross appears around the horizon. "
How can people imagine this white cross?
"All the witty people who are somewhat familiar with natural phenomena, as soon as they saw our entoptic cube between the mirrors, each time vividly exclaimed the resemblance to the Chladnian figures without even thinking about it."
literature
-
Johann Wolfgang von Goethe : On the theory of colors. 2 vol. Cotta, Tübingen 1810.
- Vol. 1. Cotta, Tübingen 1810. ( digitized and full text in the German text archive )
- Vol. 2. Cotta, Tübingen 1810. ( digitized and full text in the German text archive )
- Rupprecht Mathaei u. a. (Ed.): Goethe - The writings on natural science . Hermann Böhlaus Nachf., Weimar 1951, Complete edition with explanations published on behalf of the German Academy of Natural Scientists Leopoldina
- First section, third volume: Contributions to optics and the beginnings of color theory, 1961 (usually abbreviated as LA I.3)
- First section, fourth volume: On the theory of colors, didactic part and tables, 1973 (usually abbreviated as LA I.4)
- First section, fifth volume: On the theory of colors, polemical part, 1958 (usually abbreviated as LA I.5)
- First section, sixth volume: On the theory of colors, historical part, additions and explanations, 1959 (usually abbreviated as LA I.6)
- First section, seventh volume: On the theory of colors, table volume, 1957 (usually abbreviated as LA I.7)
- First section, eighth volume: Naturwissenschaftliche Hefte, 1962 (usually abbreviated as LA I.8)
- Gerhard Ott / Heinrich O. Proskauer (ed.): Johann Wolfgang Goethe: Color theory. Free Spiritual Life, Stuttgart 1992, ISBN 3-7725-0702-6 (Vol. 1-3), ISBN 3-7725-0838-3 (Vol. 4-5).
- Wolfgang Buchheim : The color theory dispute between Goethe and Newton in a scientific-historical perspective . Akademie-Verlag, Berlin 1991, ISBN 3-05-501275-5 (Vol. 123, No. 1).
- Anne Hardy: Goethe's color theory reloaded. The poet as an exploratory experimenter. In: Research Frankfurt. Vol. 32, No. 2, 2015, ISSN 0175-0992 , pp. 124–127 ( PDF file; 283 KB ).
- Felix Höpfner: Science Against Time. Goethe's theory of colors from the perspective of the history of reception. Winter, Heidelberg 1990, ISBN 3-533-04306-1 (also Diss., Univ. Berlin, 1989).
- Wilfried Liebchen: Goethe's theory of colors. Sandberg-Kilianshof 1999, ISBN 3-9802142-6-5 .
- Werner Heisenberg : The Goethean and Newtonian color theory in the light of modern physics . In: Geist der Zeit , 19 (1941), from p. 261. In: Changes in the foundations of natural science . Hirzel, Stuttgart 1959.
- Maurice Martin: The controversy over the theory of colors. Clear presentation of the research paths of Newton and Goethe. Novalis Verlag, Schaffhausen 1979, ISBN 3-7214-0055-0 .
- Olaf L. Müller : "More light". Goethe and Newton in a dispute over colors . S. Fischer, Frankfurt am Main 2015, ISBN 978-3-10-403071-5 .
- Albrecht Schöne : Goethe's theology of colors . Beck, Munich 1987, ISBN 3-406-32361-8 .
- Reinhold Sölch: The evolution of colors - Goethe's theory of colors in a new light . Seemann, Leipzig 1998, ISBN 3-363-00699-3 .
- Gero von Wilpert : Goethe-Lexikon (= Kröner's pocket edition . Volume 407). Kröner, Stuttgart 1998, ISBN 3-520-40701-9 , p. 9 (last entry: Franciscus Aguilonius ).
Web links
- Full text of the "theory of colors" (1810)
- Goethe's theory of colors as a Zeno full text
- Olaf L. Müller on the dispute between Newton and Goethe
- Goethe's black and white cross
Individual evidence
- ↑ Quoted from Hans Wohlbold (ed.): Goethe's color theory . Eugen Diederichs, Jena 1928.
- ↑ Johann Wolfgang von Goethe: On the theory of colors, didactic part (= draft of a theory of colors), in Goethe - The writings on natural science (Leopoldina edition), first section, fourth volume (LA I.4)
- ↑ Johann Wolfgang von Goethe: On the theory of colors, polemical part (= revelation of Newton's theory), in Goethe - The writings on natural science (Leopoldina edition), first section, fifth volume (LA I.5)
- ↑ Johann Wolfgang von Goethe: On the theory of colors, historical part (= materials on the history of the theory of colors), in Goethe - The writings on natural science (Leopoldina edition), first section, sixth volume (LA I.6)
- ↑ Johann Wolfgang von Goethe: On the theory of colors, tables , in Goethe - The writings on natural science (Leopoldina edition), first section, seventh volume (LA I.7)
- ↑ Goethe Society (Weimar): Goethe Yearbook , Volume 123, Page 120
- ^ German biography - online version, NDB article Mollweide . (PDF) Retrieved April 8, 2020 .
- ↑ See also Olaf L. Müller: Goethes Pech with Schelling (PDF; 827 kB), Section 3.2
- ↑ Quoted after 1810 color theory - historical part. In: Art Quotes. Retrieved March 18, 2013 .
- ↑ Quoted according to the confession of the author. (No longer available online.) In: Farben-Welten: Zu Goethe's color theory. Johannes Onneken, archived from the original on December 4, 2012 ; accessed on October 4, 2019 .
- ↑ See also Lutz Wenke u. a .: Sun and Truth freely based on Goethe ( Memento from February 25, 2014 in the Internet Archive ) (PDF; 305 kB)
- ↑ Quoted from Johann Wolfgang von Goethe @ www.Wissen-im-Netz.info 24. Zahme Xenien. Retrieved March 18, 2013 .
- ^ Johann Wolfgang von Goethe: On the theory of colors, didactic part (= draft of a theory of colors), in Goethe - The writings on natural science (Leopoldina edition), first section, fourth volume, §331 / 2. See also Olaf L. Müller: “More light”. Goethe and Newton in a dispute over colors . S. Fischer, Frankfurt am Main 2015, ISBN 978-3-10-403071-5 , Chapter II.2
- ↑ at projekt-gutenberg.org "About Goethe's scientific work" Lecture 1853 with a postscript 1875.
- ↑ Werner Heisenberg: The Goethean and Newtonian color theory in the light of modern physics . In: Geist der Zeit, 19 (1941), from p. 261. In: Changes in the foundations of natural science . Hirzel, Stuttgart 1959
- ↑ Martin indirectly quotes Heisenberg, cf. Marice Martin: The controversy about the theory of colors , Novalis Verlag, 1979, p. 88
- ↑ Sabine Schimma: View training. Aesthetics and Experiment in Goethe's Color Studies. Böhlau-Verlag 2014. ISBN 978-3-412-21618-4 . P. 57
- ↑ Friedrich Steinle: The next to the next: Goethe, Newton and the experiment. In: Philosophia naturalis . Archive for natural philosophy and the philosophical border areas of the exact sciences and the history of science. 39, 1, 2002, pp. 141-172.
- ↑ Matthias Rang 'Phenomenology of Complementary Spectra'. Phenomenology in Natural Science, Vol. 9, Berlin 2015, ISBN 978-3-8325-3974-0
- ^ Matthias Rang, Oliver Passon, Johannes Grebe-Ellis: 'Optical Complementarity. Experiments on the symmetry of spectral phenomena. ' Physik Journal 16 2017 No. 3 pp. 43–49
- ↑ Theodor Haering : "The moon roars through the Neckar valley ..." A romantic walk through Tübingen at night along with all sorts of useful and entertaining considerations . Wunderlich, Tübingen 1935, p. 66.
- ↑ Silke Henke, Alexander Rosenbaum: Duality in harmony. The correspondence between Schiller and Goethe. Klassik-Stiftung, Weimar 2009, ISBN 978-3-7443-0146-6 , p. 48 and 50.
- ↑ Hans-Günther Thalheim (Ed.): Friedrich Schiller. Complete Works. Volume 1: Poems. Structure, Berlin / Weimar 1980, p. 845.