C. This designation is chosen for purposes of convenience, and for limiting,' the discussion of the system C to those characters which he wishes to lay stress upon. The system C appears to be really the brain, but the word brain has many associations and suggestions which Avenarius wishes to leave out of account.
The system C is conceived as situated in the world among objects, from which it receives stimuli of various sorts, to many of which the reaction is a cognition. The undertaking is chiefly a psychology of cognitive experience, and accordingly non-cognitive reactions are left out of account. Avenarius states the situation as follows:
"Let any part of our environment be in such a relation to human individuals that when the former is a.s8umed, the latter state an experience; 'something is experienced, something is an experience or is a product of experience, or depends upon experience.'"[1]
The statements of experience are called E-values, the stimuli themselves are called R-values (Reiz). An E'- value depends directly not upon any R-value, but upon the system C, and any particular E-value is a consequence primarily of the constitution of C at the time when it gave expression to E.
Changes of some sort certainly take place in the brain. We say that tissue is broken down and built up. The process of wear and tear we believe to be due in great part, at least, to physiological excitations due to the world without. The rebuilding of tissue depends, we are sure, upon the blood-supply to the brain. We are familiar with feelings of exhaustion and of recovery of vigor, and we are reasonably sure that these feelings depend on corresponding conditions of the brain, and that between the condition which accompanies a loss of vigor and that which accompanies the feeling of restored vigor a series of states of the brain intervenes. We know also that there can be too much nourishment of the whole organism and presumably of the brain and we know that the excess can be worked off, that is, that a certain destruction of brain tissue brings back a normal condition of that organ, a point of balance between nourishment and work which we would preserve if we could. This ideal point of balance about which we seem continually to oscillate, Avenarius calls the 'Vitalerkaltiingsmaximum,' or the point of complete vital preservation. When that point is reached, the system C is in a state of stability. Such a point we do seem to pass and repass continually.
We may regard this condition of stability within C as the balance of two factors, one of them all those influences which make for the exhaustion of C, the other, the influences which make for the restoration and nourishment of C. The former of these, being the sum of
- ↑ 'Kr. der R. Erf.,' I., p. .3.
