![]() Light spectrum, from Theory of Colours – Goethe observed that colour arises at the edges, and the spectrum occurs where these coloured edges overlap.
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Author | Johann Wolfgang von Goethe |
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Original title | Zur Farbenlehre |
Translator | Charles Eastlake [[1]] |
Language | German |
Publisher | John Murray |
Publication date
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1810 |
Published in English
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1840 |
ISBN | NA Invalid ISBN |
Theory of Colours (original German title, Zur Farbenlehre) is a book by Johann Wolfgang von Goethe published in 1810. The work comprises 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) an historical section. It contains some of the earliest and most accurate descriptions of phenomena such as coloured shadows, refraction, and chromatic aberration.
Its influence extends primarily to the art world, especially among the Pre-Raphaelites. J. M. W. Turner studied it comprehensively, and referenced it in the titles of several paintings (Bockemuhl, 1991[1]). Wassily Kandinsky considered Goethe's theory, "one of the most important works." [2].
Although Goethe's work was never well received by physicists, a number of philosophers and physicists have been known to have concerned themselves with it, including Arthur Schopenhauer, Kurt Gödel, Werner Heisenberg, Ludwig Wittgenstein, and Hermann von Helmholtz. Mitchell Feigenbaum had even convinced himself that 'Goethe had been right about colour!' (Ribe & Steinle, 2002 [3]).
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[4]. Goethe's concern was not so much with the analytic measurement of colour phenomenon, as with the qualities of how phenomena are perceived. Science has come to understand the distinction between the optical spectrum, as observed by Newton, and the phenomenon of human colour perception as presented by Goethe.
It is hard to present Goethe's "theory," since he refrains from setting up any actual theory; "its intention is to portray rather than explain" (Scientific Studies [5]). 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."[6]
[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
"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 [7]). As such, he would reject both the wave and particle theories because they are conceptually inferred and not directly perceived by the human senses.
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
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 [8])
In 1740, Louis Bertrand Castel published a criticism of Newton's spectral description of prismatic colour[9] in which he observed that the colours of white light split by a prism depended on the distance from the prism, and that Newton was looking at a special case, an argument that Goethe later developed.[10]
It was in the 1780s when Goethe was asked to return a prism which had been on loan from the Privy Councillor Buettner in Jena. As he did so, he paused to take a look through the prism – and what he saw led him to a comprehensive study of light phenomena, culminating in The Theory of Colours.[11]
At the time, it was already known that the prismatic phenomenon is a process of splitting up the colourless (white) light into colours. Newton's theory stated that colourless light already contains the seven colours within itself – and when we direct this light through a prism, the prism separates what is already there in the light – the seven colours into which it is analyzed.
Goethe reasoned: In such way the phenomena are interpreted, but this is not the primal or complete phenomenon. A look through the prism shows that we do not see white areas split evenly into seven colours. Rather, we see colours at some edge or border-line.
Goethe therefore concluded that the spectrum is a compound phenomenon. Colour arises at light-dark boundaries, and where the yellow-red and blue-violet edges overlap, you get green.
Goethe's studies of colour began with subjective experiments which examined the effects of turbid media on the perception of light and dark. He observed that lights seen through a turbid medium would appear yellowish, and darkness seen through a turbid medium that had been lightened would appear blue.
Starting from these observations, he began numerous experiments, observing the effects of darkening and lightening on the perception of colour in many different circumstances.
For Goethe, light is "the simplest most undivided most homogenous being that we know. Confronting it is the darkness" (Letter to Jacobi). Unlike his contemporaries, Goethe didn't see darkness as an absence of light, but rather as polar to and interacting with light.
Based on his experiments with turbid media, Goethe characterized colour as arising from the dynamic interplay of darkness and light. The editor of the Kurschner edition of Goethe's works gives the following analogy:
Goethe writes:
When viewed through a prism, the orientation of a light-dark boundary with respect to the prism 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).
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. 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 anticipated Ewald Hering's Opponent process theory [2] 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 [15]).
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. [16]
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, all the colours already exist in white light, and the prism merely fans them out according to their refrangability. 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.
Goethe's reification of darkness has caused almost all of modern physics to reject Goethe's theory. Both Newton and Huygens defined darkness as an absence of light. Young and Fresnel combined Newton's particle theory with Huygen's wave theory to show that colour is the visible manifestation of light's wavelength. Physicists today attribute both a corpuscular and undulatory character to light, which is the content of the so-called Wave–particle duality. Curiously, since the crux of Goethe's theory is tied to what is experiential, he would reject both the wave and particle theories since they are conceptually inferred and not directly perceived by the human senses.
"Newton explains the fact that all the colors appear only when the prism is at a certain distance from the screen, whereas the middle otherwise is white... [by saying] the more strongly diverted lights from the upper part of the image and the more weakly diverted ones from the lower part fall together in the middle and mix into white. The colors appear only at the edges because there none of the more strongly diverted parts of the light from above can fall into the most weakly diverted parts of the light, and none of the more weakly diverted ones from below can fall into the most strongly diverted ones." (Steiner, 1897 [17])
Qualities of Light | Newton (1704) | Goethe (1810) |
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Homogeneity | White light is composed of coloured elements (heterogeneous). | Light is the simplest most undivided most homogenous thing (homogenous). |
Darkness | Darkness is the absence of light. | Darkness is polar to, and interacts with light. |
Spectrum | Colours are fanned out of light according to their refrangibility (primary phenomenon). | Coloured edges which arise at light-dark borders overlap to form a spectrum (compound phenomenon). |
Prism | The prism is immaterial to the existence of colour. | As a turbid medium, the prism plays a role in the arising of colour. |
Role of Refraction | Light becomes decomposed through refraction, inflection, and reflection. | Refraction, inflection, and reflection can exist without the appearance of colour. |
Analysis | White light decomposes into seven pure colours. | There are ony two pure colours – blue and yellow; the rest are degrees of these. |
Synthesis | Just as white light can be decomposed, it can be put back together. | Colours recombine to shades of grey. |
Particle or Wave? | Particle | Neither, since they are inferences and not observed with the senses. |
Colour Wheel | Asymmetric, 7 colours | Symmetric, 6 colours |
Today, Goethe's Theory of Colours is still remarkable for its phenomenological observations.
His claim that colour arises from the interplay of light and dark has caused almost all of modern physics to reject Goethe's theory as unscientific – yet Goethe was consistent in his approach.
Developments in understanding how the brain interprets colours, such as colour constancy and Edwin Land's retinex theory bear striking similarities to Goethe's theory (Ribe & Steinle, 2002 [20]).
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.
“ | As to what I have done as a poet... I take no pride in it... but that in my century I am the only person who knows the truth in the difficult science of colours – of that, I say, I am not a little proud, and here I have a consciousness of a superiority to many. | ” |
— Johann Eckermann, Conversations of Goethe, (tr. John Oxenford), London, 1930, p.302 |
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