Colors therefore arise where dark and light work together. It is the same type of phenomenon, for instance, as the way the human etheric body is inserted into the muscles and into the eyes. It is inserted into a muscle in such a way as to blend with the functions of the muscle; this is not so when it is inserted into the eye. In the isolated eye, it remains comparatively independent. Consequently, the astral body can come into very intimate union with the portion of the etheric body that is in the eye. While the astral body is inserted into both muscle and eye, it is inserted in a different way in each. It is so inserted into the muscle that it goes through the same space as the physical bodily part and is by no means independent. It is inserted into the eye such that it works independently, though the space is filled by both in both cases. It is but half the truth to say that our astral body is there in our physical body. We must ask how it is in it. Ingredients can interpenetrate each other and still be independent. So too, you can unite light and dark to get grey; then they interpenetrate as do the astral body and muscle. Or on the other hand light and dark can so interpenetrate as to retain their several independence as is the case with the astral body and the physical organization in the eye. In the one instance, grey arises; in the other, color.³⁸

When some of Steiner's audience expressed difficulty in comprehending what he had given, he told them they would understand it better by and by, for he would have to go more into the phenomena of light and color. It was, he said, the real piece de resistance in relation to the rest of physics. It would not be found, he said, in the textbooks, and it remains so to this day. His objective was to explain the interplay of light and darkness as well as the polarity of color. He assigned the difficulty his hearers were having to their hankering after a kinetical treatment of light and color, a mental habit instilled by the "strange" education one is made to go through (as against the type, for instance, given in the Waldorf Schools, whose initial faculty were his audience). People tend to restrict their thinking to the arithmetical, spatially formal and kinematical, and when called upon to think in terms of quality they get stuck because of the unnatural direction pursued by modern science (little seems to have changed in this respect).

Steiner explains how Goethe was also told by the physicists that when you let colorless light go through a prism it is analyzed and split up into its seven component colors. Goethe borrowed some apparatus to examine for himself and came up with some surprising phenomenal contradictions to that theory. For when he let the light pass through the prism, the only place where he could see any color at all was at some edge or border line (as above). The phenomena just was not as described to him. He saw that it is not that the light is split up. In point of fact he saw that the colors occur not because the light is split up but because the image projected through the aperture has edges where the light adjoins the dark. For there is darkness outside the circular patch of light, while it is relatively light within it. The colors thus, to begin with, make their appearance purely and simply as phenomena at the border between light and dark. This, and this alone, is the primary phenomenon. We are no longer seeing the original phenomenon when by reducing the circle in size we get a continuous sequence of colors. The latter phenomenon only arises when we take so small a circle that the colors extend inward from the edges to the middle. In both instances, the colors arise at the borders where light and dark flow together.

I wonder how many of my readers had the same reaction when they were introduced to this phenomenon in their introductory physics study of the so-called light spectrum. I couldn't understand, if light comprised seven colors as we were told, why we still saw regular light in the middle when all seven colors were present. If they represented the fullness, the pleroma (as in the case of the Elohim in Jn 1,16), as indicated, then why did we still see the light as well? It didn't really make sense, but it was never explained—because it conflicted with the (kinetic, ideal) scientific theory.

The point, says Steiner (a la Goethe), is not to bring in theories but to confine ourselves to the given facts. In these phenomena, not only are the colors at the edges, but the entire cone of light is also laterally displaced.

Next Steiner puts two prisms together, one positioned the same as before and the other placed on top of it as in Figure 3:

FIGURE 3

FIGURE 4

When the stream of light is made to pass through the central part, as in Figure 3, it is pushed together, reduced in size, and the red is on the outside with the violet in the middle.

Steiner then substitutes a convex lens (which is the same as the two prisms with their surfaces curved instead of plane) and the effect is generally the same. If the light passed through an ordinary plate of glass or water, the cylinder of light would just go through and a simple picture of it on the screen would be the outcome (only slightly dimmed for the passage depending upon the clarity of the glass or water). Not so if a lens is used.

He then sets up a concave lens (or prism setting) as in Figure 4. Here the circle is considerably enlarged but violet and bluish colors appear at the upper and lower edge with red in the middle—just the opposite of what it was before—again with the intermediate colors.

What do we see from these phenomena? How can it be that the light is thrust apart (in the latter experiment)? It can only be through the fact that it has less matter to go through in the middle and more at the edges, so that it passes through more easily in the middle retaining more of its force after passing through. The facts are the facts. What is seen has nothing to do with the light. It is simply brought about by the light's going through the slit. And if one says that the light moves in this or that direction, that again has nothing to do with the light as such, for if the source of light is moved upward, the light that falls on the slit would move thus and so, which again would not concern the light as such. People have formed a habit of drawing lines into the light, and from this habit they have gradually come to talk of "light rays." In fact, says Steiner, we never have to do with light rays; what we have to do with is a cone of light due to the aperture through which we caused the light to pass.³⁹