In the first chapter of this investigation, we set forth the following aphorism from Goethe:
The highest were to grasp that everything phenomenal is already noumenal. The blue of the heavens proclaim the principle of colour-theory. A man should not look past the phenomena, but allow himself to be instructed by them. 
We suggested that Goethe’s maxim, which we may also capture in an abbreviated form with the term “the open secret” (das offenbare Geiheimnis), can serve to unlock the chamber of our understanding, provided we recognise the above as the golden key that it is. Otherwise, it will be for us a mere sequence of words, of which there are doubtless more pleasing ones. We also noted that Goethe compared many speculative scientific thinkers of his day, who insistently seek behind phenomena for their explanation, to little children who turn a mirror around for the cause of their own reflections. As the Goethean maxim suggests, however, the proper approach is to recognise the essence of the phenomenon in the phenomenon itself, which in this distinction from other phenomena, is also a relation to them. Thus, the truth of a phenomenon is in the phenomenon itself and in it relation to other phenomena. This conception contrasts to the approaches that Goethe criticises, which postulate an explanation for phenomena behind them, or outside of what can be experienced. Goethe enjoins us to recognise that the facts mean something and that what they mean is the theory, or the Urphänomen (“archetypal phenomenon”). Let us explore this notion in respect to Goethe’s studies in colour. In this project, we will enlist Newton as a foil, since he epitomises just the approach that Goethe meant to contest (as the latter made abundantly clear in the polemics against the great English physicist, which he included in Zur Farbenlehre. This is hardly surprising as the Newtonian doctrine was the prevailing one in Goethe’s day as in our own). 
Goethe’s interest in colour theory was kindled by an effort to understand the technique of painters. He soon realised that the artists of his day were capable of enlisting intuitive knowledge of colour theory in their compositions, but not of bringing the theory to the point of articulation. Goethe set about his studies by attempting to observe the behaviour of colour under various conditions, which he expressively described as “the deeds and suffering of light.” This was an attempt to recognise the archetypal phenomenon that indwellt all of its iterations. The aphorism above alludes to such a manifestation of archetypal phenomenon in the blue of the sky. In fact, every visual experience is a revelation of the archetypal phenomenon of colour to the one who, like Goethe, has won through to the recognition of it. In a way, this is obvious: we can only perceive what we can conceive. The contrapositive is a non-thing for us and therefore not a potential object of perception.
In respect to the expansive setting that Goethe’s aphorism evoked, Newton’s testimony of his own studies provides a stark and illustrative contrast. Whereas Goethe entered into optics through the door of art, Newton came through the door of technology: seeking “the perfection of Telescopes.” In a letter of 1671, Newton describes how his foray into studies of light and colour began as a diversion from grinding lenses.  In fact, the spectrum phenomenon was a problem for lenscraft in that it distorted the image’s clarity. Thus, Newton’s original involvement in colour came about because he was trying to be rid of it. Still, the spectrum phenomenon sparked his interest and he quickly devised the following experiment to demonstrate an hypothesis as to the cause of the spectrum, which he apparently arrived at before performing the following Experimentum Crucis (for this reason, it is more of a demonstration than an experiment):
In a darkened Room make a hole in the shut of a window, whose diameter may conveniently be about a third part of an inch, to admit a convenient quantity of the Suns light: And there place a clear and colourless Prisme, to refract the entring light towards the further part of the Room.
Newton’s approach could hardly be more at odds with Goethe’s. Whereas Goethe seeks to observe the deeds and sufferings of light in manifold conditions in order to understand colour, Newton shuts himself in a darkened room to prove an understanding he had already devised. In the first instance, the scientist seeks to understand by contemplating the manner in which the phenomenon changes amongst diverse contexts. In the second instance, the phenomenon is first divorced from its context in the interest of isolating the variable, such that a foregone hypothesis can be verified. That such a procedure has become second nature to the practice of science today does not prove that it is the only manner to conduct scientific inquiry, nor that it is the best. In fact, by dividing a phenomenon from its context, one has arguably substituted one’s original object of inquiry with a different one. In the last chapter, we explored this impulse of abstraction and evaluated its consequences in an attempt to discern its proper role. To borrow the example from that section: the anatomist’s liver is not the Thomist’s. Goethe expresses a similar sentiment in respect to a butterfly: “The poor creature trembles in the net, rubs off its most beautiful colours; and even if one captures it unharmed, it still lies there finally stiff and lifeless; the corpse is not the whole creature; something else belongs to it, a main part, and in this case as in every other, a most major main part: its life….” (July 14, 1770) From Goethe’s perspective, which perhaps may become our own as well, it is impossible to study a living butterfly with a method that is only suitable to dead one. Goethe’s quote describes how the entomologist is not studying a butterfly anymore, but a specimen. In principle, one has rent the phenomenon from its context while subsequently sustaining the illusion that it should remain the same phenomenon after the excision. Goethe expresses the same spirit in verse in Faust:
Who would know the living and describe it well,
Seeks first the spirit to expel.
Then holding sundry parts in hand
He lacks, alas! the spirit’s band. 
Also in verse, Keats offered a still pithier and more pertinent encapsulation of this sentiment when he wrote in “Lamia”:
Do not all charms fly
At the mere touch of cold philosophy?
There was an awful rainbow once in heaven:
We know her woof, her texture; she is given 
And continued to tell of the rainbow how science would “unweave” it. This dismemberment is accomplished by designating the phenomenon of colour as a “secondary quality” and proceeding to hypothesise non-qualitative processes to account for it.  Newton admitted that “to determine more absolutely, what Light is, after what manner refracted, and by what modes or actions it produceth in our minds the Phantasms of Colours, is not so easie. And I shall not mingle conjectures with certainties.” With this concession, however, he straightaway set about to “peer behind the phenomenon,” as it were. More specifically, he proceeded to explain the various qualifications of light according to an hypothesis that he had already devised: namely, by appeal to quantifications of refrangeability. By the time of the publication of Opticks in 1702, some thirty years after the letter quoted above, Newton had modified his hypothesis to affirm that, rather than refrangeability, corpuscle (i.e. atom or particle) size was to account for the divers colours of the spectrum. In this manner, Newton revealed himself to be the forefather of conceptions in modern physics, which alternatively conceptualises light as a wave and a particle. As we indicated in the first chapter of this exploration, such quantitative designations correlate with, though do not explain, the various perceptible colours by mapping them onto the electromagnetic spectrum, of which the visible spectrum constitutes a small portion ranging from a wavelength of 400 nanometers at the violet end to 700 at the red end. The latter is conceived of as a quantum by contemporary physics, and metaphorically described as a particle or “corpuscle” while it is in fact a quantity of energy, which for physicists means “a conserved property (i.e. can not be created or destroyed) that can be imparted to objects as a measure of work.” One has run ahead of the moment of this exploration, however, by several centuries and therefore we will return to Newton’s experiments.
From his “darkened Room” Newton was able, with the imposition of “a clear and colourless Prisme,” between the far wall and the single ray of “the Sun’s light,” to produce the familiar seven-toned spectrum. From this fact, he proceeded to infer that the sunlight itself already contained the colours in an impure state and that the prism served only to disentangle these various strands. Light, concluded Newton, consists in an “Heterogeneous mixture of differently refrangible Rays.” From the fact that every third-grader learns this fact in primary school today, we should not necessarily infer that it is true. Indeed, just as the mere fact that an hypothesis manages to save the appearances does not ipso facto imply that it is true, so neither does the fact that the same hypothesis is proffered to schoolchildren in elementary science class. Other explanations than Newton’s can account for the appearances of the rainbow out of sunlight,  and as a rule, children are indoctrinated into the dominant intellectual paradigm of their respective culture. In this exposition of Goethean science, we are exploring another possibility.
Comparing Newton’s assertion that light consists in an “Heterogeneous mixture of differently refrangible Rays,” Goethe’s conception strikes us as almost the reverse. “Das Licht,” wrote Goethe, is “the simplest most undivided most homogeneous being that we know. Confronting it is the darkness.”  How could two obviously competent thinkers arrive at such contrasting conceptions? We have already implied the answer above. Goethe and Newton adopt fundamentally different approaches to science in general, which their eventual findings bear out and of which their respective investigations into colour provide eminent examples. Scientific findings invariably supervene on the method enlisted in the attempt to discover them. Further, the method itself supervenes on the nature of the scientist: not everyone looks with the same eyes, as it were. Undertaking Goethean science means training oneself to see differently. As a result, the same phenomena reveal themselves in a new manner and, as a result, they are no longer the same phenomena. Goethe himself expresses this notion in respect to Galileo’s ability to recognise the law of isochronous pendular motion in the chandelier in the Tower of Pisa:
For a genius, one case serves for a thousand, in that he developed for himself from the swinging church-lamps the doctrine of the pendulum and of the fall of bodies. In science everything depends on what one calls an aperçu, on becoming aware of what actually lies at the foundation of the appearance.
An aperçu is a keyhole to insight, through which the scientist may peer, but “if we would succeed, to some degree, to a living view of Nature, we must attempt to remain as active and as plastic as the example she sets for us.”  The aperçu as the keyhole, our own minds must themselves assume the form of the golden key. This we can only manage if we know what that form is, in contrast to its mere matter. And in this, we must allow the phenomenon in question to be our mould.
Indeed to accomplish this demands of the scientist an renunciation of his rigid thought-forms, which are in truth only the strictures of his egoism. Hamlet’s advice to the dramatists that they “suit the action to the word, the word to the action,” might as well have been to the one who undertakes and investigation of natural phenomenon:
…whose end, both at the
first and now, was and is, to hold, as ’twere, the
mirror up to nature; to show virtue her own feature. 
It is hardly an accident that Shakespeare is still hailed today by sensible people as a supereminent figure in the history of English literature. Likely his legacy would not have been so great had he not employed the same archetypal cognitive method as Goethe. Shakespeare was able to contemplate characters and meanings in the manner that Goethe also sought to employ in respect to the phenomena of Nature. Art and science differ in this: that the former incarnates meaning into a given medium of expression such that that medium then begins to enunciate the very meaning by which it was first informed, while the scientist himself attempts to become the mouthpiece of Nature; to enunciate those meanings by which the world of Nature was originally informed. In a manner, art is not a thing but a state of mind. More precisely, art is an intentionality, both in its generation and in its appreciation. One must approach the phenomenon with the intentionality that it means something. If one fails to do this, then art becomes commodity. By the same token, when one assumes Nature does not mean, science becomes Newtonian. To Goethe, the notion that a scientist should shut himself in a “darkened Room” to study colour was as abhorrent as the one who wanted to study living butterflies by dissecting dead ones. Whereas Newton’s conception of science involved closing off a phenomenon in isolated conditions and then picking the lock to Nature’s chamber with the tools of telescopes and mathematics, Goethe conceived of science as an attempt to discern Nature’s meaning as it is written in the great script that is the phenomenal world: “Hodie legimus in libro experientiae” (“today we read in the book of experience.”).  In Goethe’s view, no more can one expect to grasp the meaning of a text—like Goethe’s maxim, which sounded the keynote of this chapter, for instance—through an analysis into its discreet characters, than can one expect to understand the world of Nature by splitting it into its component parts.
When he brought to bear this intentionality to light and colour, Goethe immediately found himself in opposition with Newton’s adherents: “almost by instinct, I said aloud to myself that the Newtonian doctrine was false,” Goethe recalled. To Goethe’s mind, light was a necessary condition for colour, but not of itself a sufficient one. If it were also sufficient, Newton would have had no need to shut himself in a darkened room in order to produce the colour spectrum, since the sunlight itself already ostensibly contained an “heterogenous mixture of differently refrangible Rays.” Goethe perceived that the appearance of colour required the presence of shadow. Thus, together with light, Goethe also identified darkness as a necessary condition of colour. The colours, for Goethe, were the daughters of their relation. Goethe described light as “the simplest most undivided most homogeneous being that we know. Confronting it is the darkness.” 
He contrasted his conception to the prevailing doctrine of his day, which like our own time, is that set forth by Newton and his adherents, who “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.”  In contrast to the Newtonians, which is the standard even today, Goethe did not attempt to conceptualise light and a thing or a substance or a quantum of energy. In fact, from Goethe’s perspective, light did not pertain to the realm of visible and created things. Light, rather was the condition of visibility; itself invisible but the principle from which all potentially visible entities derive this quality. What is seen is colour; that by which it is seen is light.
To again recall the spirit of Goethean science, as expressed in the maxim that sounded the keynote for this exploration, whether the above conception is true will not be settled by argument or disputation. If it is true, then it is an open secret, which awaits only the ripening of our faculties that we may recognise it. This is accomplished through theoria and not through theorising.
 Maximen und Reflexionen no. 488, 1833
Das Höchste wäre, zu begreifen, daß alles Faktische schon Theorie ist. Die Bläue des Himmels offenbart uns das Grundgesetz der Chromatik. Man suche nur nichts hinter den Phänomenen; sie selbst sind die Lehre.
Another translation, by the letter, reads roughly as follows:
The highest were to grasp that everything factual is already theory. The blue of the heavens reveals the fundamental laws of chromatics. A man should not seek behind the phenomena; they themselves are the teaching.
 Goethe, Johann Wolfgang von (1995). Scientific Studies (vol. 12 of Goethe: The Collected Works), edited and translated by Douglas Miller. Princeton NJ: Princeton University Press.
 Philosophical Transactions of the Royal Society, No. 80 (19 Feb. 1671/2) http://www.newtonproject.ox.ac.uk/view/texts/normalized/NATP00006
 Part I, Study
 Ernst Lehrs described this method as the “one-eyed, colour-blind approach” to science in Man or Matter, London 1951; Klostermann, Frankfurt am Main 1953; 3rd edition 1987.
 Cf. Robert Hooke’s Critique of Newton’s Theory of Light and Colors (delivered 1672):
But, how certain soever I think myself of my hypothesis (which I did not take up without first trying some hundreds of experiments) yet I should be very glad to meet with one experimentum crucis from Mr. NEWTON, that should divorce me from it. But it is not that, which he so calls, will do the turn; for the same phænomenom will be solved by my hypothesis, as well as by his, without any manner of difficulty or straining: nay, I will undertake to shew another hypothesis, differing from both his and mine, that shall do the same thing…though yet, methinks, all the coloured bodies in the world compounded together should not make a white body, and I should be glad to see an experiment of that kind done on the other side.
Thomas Birch, The History of the Royal Society, vol. 3 (London: 1757), pp. 10-15.
That observations, even those which might prima facie seem to disprove a given theory, can always be accommodated by it, is sometimes called the Quine-Duhem Thesis after work in this area by those philosophers.
 Letter to Friedrich Jacobi
 From the essay “Formation and Transformation”
 Act III; scene ii
 One is reminded of the unforgettable words with which St. Bernard of Clairvaux opened one of his sermons: “Hodie legimus in libro experientiae” (“today we read in the book of experience”)
 Letter to Jacobi
 Conversations with Eckermann. Cf. also note 7.