‘to my eye, or for me, it is red’.[1] By this limiting addition the contradictions involved in the absolute standpoint are removed. So long as the errors of introjection are avoided, this relativism is perfectly unambiguous, and it is also the only possible or consistent attitude. But when misled by a dualistic distinction between the absolute and the relative, between appearance and reality, we ask: What is the object in and for itself?—we raise an unreal, because self-contradictory, problem. And it does not matter whether in answering that question we take up a positive or an agnostic attitude. The two statements—‘The object in and for itself is neither red nor black’; ‘The object in and for itself we do not and cannot know’—are alike untenable.
The sole remaining question, properly stated, is not how the brain, viewed as an external and independent reality, is related to consciousness as something distinct from the brain and dependent upon it, but why our experience as a whole should vary together with one particular part of itself. And, as we have seen, Avenarius seems to hold that that problem is on a level with the question, why the three angles of a triangle should vary together with one another. The laws of logical functional relation between experience and the brain, when discovered, are ultimate facts, beyond which nothing remains to be known. Even the suggestion of the problem implies unconscious reminiscence of dualistic metaphysic. In his Kritik der reinen Erfahrung Avenarius, as I have also already indicated, has formulated the laws which he conceives as holding between the brain and the world which includes it, that is to say, the laws according to which the brain as a reacting agent either neutralises or uses for its self-maintenance the stimuli which are constantly arising from its own internal changes and from the spatial world within which it lies. In accordance with these laws it progressively adapts itself by internal organisation to a more and more comprehensive environment, and so preserves itself through change in relative equilibrium. And as there is a logical functional relation between the states of the brain and our experience as a whole, these laws express the ultimate truth regarding the self in its relation to reality.
I cannot here enter upon Avenarius’ ‘physiology of knowledge’ beyond indicating in the briefest manner how he applies his biological laws in explanation of experience as a whole. I may cite his theory of protective concepts. When the brain is unable to adapt itself to certain stimuli it drains them
- ↑ Loc. cit., § xiv.
