Thus far in our exploration of Goethean science, we have juxtaposed it against the mathematical science of Newton and the mechanical science of Helmholtz. By considering Goethean science in various contexts, we are attempting to apply the Goethean method to itself. This indeed was Goethe’s conception of science: to read the archetypal phenomenon in changing characters that it presented in the midst of varying conditions. The Urphänomen of Goethean science is patent in his approach to geology: “But if I would treat those cracks and fissures as letters, and try to decipher them and assemble them into words, and learn to read them, would you object?”  Contrary to Newton’s insistence that “hypothesis non fingo!” conventional science in the lineage of the illustrious Cambridge physicist invariably explains phenomena by appealing to invisible causes behind them which are not phenomenal, like corpuscles, waves, field properties, charge, spin, and pseudo-particles, etc…. This is inimical to Goethe’s way, as the Goethean maxim encapsulates it:
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.
The highest were to grasp that the phenomena explain themselves out of themselves. The blue of the heavens proclaims the principle of colour-theory. A man should not seek behind the phenomena, he should hearken to them. 
The blue of the daytime sky, for instance, appears as such in that the light of the sun41 is losing itself into the darkness of space. The sun appears yellow because its incident light is darkened from white to yellow (towards red) by the atmosphere. On the one pole, the sky, from blue, approaches white as the atmosphere becomes increasingly dense and therefore more resistant to the light. This resistance or turbidity appears in the form of clouds and vapour, for instance. Such a condition results in the ratio of out-streaming light and reflected light tipping to the latter side. This is also the reason that the sky at high noon appears closer to white at sea level and closer to black on the Tibetan plateau. In the latter case, more light looses itself into the distance and therefore blue metamorphoses to indigo and thence to black. Light lost is darkness, and this is why the night sky displays similar characteristics to the daytime sky at high altitude. Far-off mountains appear tinged with blue because they are not sources of light and because the atmosphere interposes and therefore creates the same effect as the blue sky. On the warm side of the spectrum, resistance or turbidity has the polar opposite effect by darkening the light instead of lightening the dark. Thus, the noontide sun on a clear day at the highest elevations or in outer space appears nearly white, while at sunset or through smoke it approaches red on the way to black.
The same archetypal polarity in the phenomenon of colour expresses itself in the flame of a candle. Considering the familiar blue and orange flame, we recognise the latter as incident light of the combustion process, and the former as light emanating into the surrounding darkness. Conventional science invokes the explanation for the blue of the flame that the combustion generates sufficient energy to excite and ionise gas molecules in the flame, while the yellow is the result of incomplete combustion and therefore radiates from incandescent soot. This is one explanation, and the reader is challenged to perform her own research on the subject. The present writer is convinced from his own experience in the matter that one can easily discover half a dozen more or less divergent explanations for this phenomenon from contemporary physics textbooks, none of which are themselves phenomenal (i.e. potential objects of experience) even in principle. In fact, there is no limit to the number of ad hoc explanations a person can invent if he is not bound to derive his explanations from the object of his observation. This is not to say that such explanations have no utility, but only that alone, they do not provide a comprehensive understanding of the facts of Nature.
If we select the explanation offered above: that more complete combustion results in the ionisation of gas molecules in the flame, let us inquire what about this makes it blue? Wavelength must be the answer given that contemporary physics has redefined colour to mean “oscillations on the electromagnetic spectrum.” Why then does the blue disappear directly the flame is observed against a white background? Admittedly, this is an uncommon situation given that candles are ordinarily observed in dark conditions. Nevertheless, the fact that the blue flame disappears against a white background can be confirmed by empirical observations. Naturally, this is not a fatal problem for a convention scientific explanation because a
theory can always be tweaked and moulded to accommodate new observations. The former, therefore, unbeholden as it is to the observable facts, can always invent an attenuating circumstance to account for discrepancies between expectation and observation. In the case above, for instance, it is easy to explain the disappearance of the blue by affirming that the human retinae lack sufficient sensitivity to discern the flame in those particular lighting conditions. Such ad hoc justifications are opposed to a Goethean approach, since they ignore the phenomenon as it presents itself and instead attempt to represent it with equations and mechanics. This betrays a fundamental mistrust of the human senses. Goethe, again, takes the opposite perspective:
Man, insofar as he employs his healthy senses, is the most perfect of physical instruments; and it is greatest misfortune of the new physics that one has sundered the experiments from the human being, tries rather to penetrate nature with artificial instruments, thus stifling what she can accomplish in an attempt to prove her. 
For Goethe, it was contradictory to doubt the testimony of the senses since the grounds for this scepticism will invariably depend on the very senses that it attempts to call into question. Goethe, therefore, saw the scientist’s task as one of educating the mind to make appropriate use of the senses, not to discount them. The fact that a roadway appears to narrow in the distance is not a flaw of the visual apparatus. Instead the latter is reflecting, with fidelity, the laws of the vanishing point in linear perspective. The fault lies with the hypothetical mind if it fails to recognise the Theorie in the Faktische and issues conjectures on insufficient grounds. The question of what the senses can provide will reëmerge in the next chapter of this exploration when we proceed to juxtapose Goethe and Kant. At this point, however, we will return to the first example of colour that we introduced above: the blue of the sky and the yellow of the sun. We presented Goethe’s perspective with the presentation of this phenomenon. The explanation from conventional science, however, remains to be noted.
Why, according to contemporary physics, does the sky appear blue? Several reasons are offered. Again, any number of hypothesis can be construed to account for a given phenomenon in the instant that “one has sundered the experiments from the human being, tries rather to penetrate nature with artificial instruments,” to recall Goethe’s words quoted above. One reason is that water droplets appear blue and the atmosphere is constituted of an high percentage of water vapour. Another reason that is offered presupposes the Newtonian theory (with elaborations by later thinkers) that white secretly contains all the colours. Before we continue to examine this second explanation, it is necessary to explore to what degree the Newtonian doctrine is justified. Ultimately, it is only possible to maintain the latter by redefining colour as electromagnetic wavelength and thereby sundering it from the experience of colour. This is precisely what contemporary optics has opted to do. Otherwise, simple experiments would reveal that a colour is always an interplay of light, of darkness, the context, and of the observer together. For instance, in red light, a strawberry appears white. In any all other lighting conditions it appears the same shade red, except in green light, in which conditions it approaches a black colour.  This would seem to cast doubt on the notion that colour is a function of the wavelength of light striking the retina in a given instance. Of
course, an explanation can always be provided by denying the fidelity of the eye, or by appealing to the frailty of human apprehension in some other respect. In my estimation, the simpler and more wholesome explanation is to say that the strawberry, being red, reflects 100% of a red light-source that falls upon and therefore appears white, while the black strawberry in green lighting appears as such because it absorbs 100%. In both cases then—the strawberry appearing white under red and black under green—the eye is providing a faithful testimony of the physical conditions and it befalls the researcher to educate his senses. This is actually a slightly misleading phrase, since it is really a matter of educating one’s mind to properly interpret the senses: “the senses never err, judgement does,” in Goethe’s words.
Bearing the contrast with the Goethean method in mind, let us consider again the answer that conventional science provides to that timeless question, “why is the sky blue?” Having first presupposed the Newtonian doctrine, conventional science then posits that the blue end of the spectrum is more susceptible to scattering by particles in the atmosphere because it has a shorter wavelength. This is often referred to as the Tyndall effect, or Rayleigh scattering, and can be demonstrated by shining white light into a semi-opaque or cloudy medium. Even smoke can sometimes serve this purpose. Viewed from the origin of the incident light or from the side, the medium appears tinged with blue. Viewed from the opposite side, the source of incident light appears yellow or red depending on the opacity of the medium. This is intended to prove that blue light is more scattered by the particles in suspension and that yellow and red light is not. This susceptibility to being scattered is then attributed to the wavelength: the longer wavelength more resolutely maintaining its course. Blue scatters sixteen times more readily than red, apparently. The reason the sky is not violet (after all, violet is understood to have a still smaller wavelength than blue) is because the human visual apparatus is not sufficiently sensitive to this wavelength or because it scatters so much that it is invisible. I leave it to the reader to consider (i) what portion of this explanation is actually observed, (ii) what portion is hypothesis based on observation, and (iii) what portion is hypothesis based on hypothesis. One only wonders, if the incident light indeed already contains all wavelengths of the spectrum, why the red cone of light is not visible from the side (since it is ostensibly not scattered), and where the yellow goes when the red appears with increasing opacity, and also why the red is not visible at first, and also why the scattering of the blue light immediately ceases to transpire directly the experiment is performed in front of a white background, etc…. Needless to say, Goethe would not appeal to any explanation of this sort because it attempts to explain what is manifest by what is conjectured. Instead, he would recognise the same Urphänomen in these derived conditions as he also reads in the book of Nature. Incident light shining outward into darkness appears blue. Incident light directly perceived darkens from white to yellow to red to black in proportion to the resistance it must overcome to reach the eye of the beholder. Goethe expresses it succinctly in Zur Farbenlehre: “Yellow is a light which has been dampened by darkness; Blue is a darkness weakened by light.” Contrary to the Newtonian doctrine, colour is the issue of light and shadow, not of light alone, and a given colour is a function of the particular conditions of their relation. Seen in this light, colour becomes a text in which are writ the principals of Nature.
 Wilhelm Meisters Lehrjahre.
 Maximen und Reflexionen no. 488, 1833.
Some other translations of the same, from earlier chapters:
∆ 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.
∆ 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.
 Both reflected light off of the earth and also incident shining into the atmosphere.
 Maximen und Reflektionen, No. 53.
 Aristotle noted the same. In Meteorology, he states:
The same effect [as in the rainbow] can also be seen in dyes: for there is an indescribable difference in the appearance of the colours in woven and embroidered materials when they are differently arranged; for instance, purple is quite different on a white or a black background, and variations of light can make a similar difference. So embroiderers say they often make mistakes in their colours when they work by lamplight, picking out one colour in mistake for another.