# 92. On the Process of Color Perception

> [Excerpt from Walter Johannes Stein's formulation of the question, from a letter to Marie Steiner, ca. August 1917: “So a living process flows into the eye: the veiled color. As soon as this touches the eye, something like a process of withering and dying occurs. [...] What remains afterwards is a process similar to what can be observed in a camera obscura. The result of this purely physical process is the retinal image. This is an image, but only for another eye. For the perceiving eye, it is a chemical process in the eye itself. But the eye is a living thing, and a chemical process in a living thing is a process of dying or reorganization. Here it is the former. Immediately, however, the astral body tries to restore what has been destroyed by causing a polar chemical process. If the incoming flow was yellow, for example, the astral body responds by producing blue.
> What we now have in our consciousness is the process of destruction. However, the process of construction appears in our consciousness when we look at a white wall after looking at a yellow one. We see a complementary blue.
> Now, apart from the fact that there may be errors in what has been said so far, questions arise:
> 1. How does this ejection of the etheric-living occur? [...]
> 2. While I know that the color yellow is perceived on the yellow object, I do not know on what the complementary blue is perceived. Does the eye really produce an objective blue? Then it should be possible to represent it on a screen, not only for the eye itself, but objectively, that is, for other eyes: I carry it. So: is the process of perception reversible? Can the eye create colors that are also visible to other eyes?"]

[Answer by Rudolf Steiner to a letter from Marie Steiner for transmission to Walter Johannes Stein:] The good man should consider the process of perception in its entirety: What happens when I perceive “yellow”?

1.) In the eye itself, from the objective point of view: a living yellow.

2.) The etheric body of the perceiving subject penetrates from within this animated yellow; as a result, the yellow, which is permeated by the external ether and is therefore animated, becomes dead yellow. There is dead yellow in the eye because its life has been displaced by the inner life (etheric body). Thus, instead of the outer animated yellow, the cognitive subject has the image of yellow animated from within, but this image contains the corpse of the yellow. So far, the process is objective-subjective. However, this would only produce an inwardly living yellow, of which the cognitive subject could not know. It could only experience its own subjective-objective, not consciously experience it.

3.) The astral body of the cognizing subject enters the subjectively and objectively revitalized yellow. The astral body produces the animated “blue” on the animated yellow; this blue is actually created within the organism, but does not spatially extend beyond the organism. So it is present:

> 1.) the astral image “blue”,
> 2.) the effect of this astral image on the etheric body - as a subjective life process,
> 3.) physiologically the physical process in the eye that has an inward, not outward, blue effect.

All this, however, does not become the object of the I-consciousness; the I only knows when the

“yellow” that has been animated in the eye

is internally attenuated (paralyzed) - then the following is present:

1.) attenuation of the life in the yellow by the I

2.) the conscious appearance of the no longer living yellow in the astral body.

3.) the astral image “blue”, which is over-illuminated by the dead yellow and therefore remains unconscious.

4.) its effect in one's own etheric body

5.) the physiological process in the eye.

If the object from which the yellow comes is now removed, the erasure of the astral image “blue” stops - and this fades away until the inner - mental, spiritual and physical organism has restored itself. But one cannot reverse the process of perception, because the “blue” is not a spatial entity, but comes from the astral body, and its physical effect remains only within the organism.

Just as the blue triggered subjectively in the inner world by the objective yellow cannot be projected objectively onto a screen, the reverse is also true: the objective process that follows a real volition cannot have an effect on the subject again. Otherwise, if one goes from A to B, it should be possible to return from B to A by means of the effect produced in the external world when the path is traveled.