accurate mental tests to candidates for mating, and so to select in accordance with adequate mental standards, racial betterment might be attained along this line: but we have no criteria which are capable of such application, and cannot foresee the time when they may be available. The important question, therefore, is whether there is an element in beauty itself which serves as an index of mental and spiritual potentiality: or whether our selection is indeed blind in this respect.
The mental life of the individual: the processes which directly involve consciousness: depend, as we now know, on the integration of the nervous system, and not on the specific activity of certain cell-groups in the brain. The nervous system is made up of myriads of nerve cells—neurons—, each one a distinct individual. These neurons form chains of communication from every sense organ to every muscle and gland. Many of these lines of communication may, at certain moments, operate in relative independence of one another. The lines which control the merely “physiological” processes usually possess a relative independence. Conscious reactions, on the other hand, are reactions of a large part, if not of the whole of, the organism: reactions in which the “nervous discharge” over a vast network of routes, is integrated, or welded, for the moment into a single function of the complex system.
