moral man or the ethical thinker regards definite relations in behavior in response to definite relations in the environment as right or wrong; while the artist or the one who enjoys artistic work appreciates definite relations and combinations as the artistic and the beautiful. Even in ordinary life where the process of selection is not so rigid as in the arts, sciences, and philosophy, still the process of attention for the maintenance of rationality is a severe judge in the rejection of unfit streams of thoughts and ideas that may present themselves in the antechamber of consciousness, as Galton terms the state of the mind. In a train of ideas, few ideas of the total mass that offer themselves are accepted, or utilized by the guiding, controlling consciousness to be acted upon in the life adjustments of the organism. This holds true not only of the material needs, but more especially of the spiritual interests of man. The higher the level of mental activity, the more definite, the more precise, the more rigid the selective process becomes. The stream of consciousness, as it rushes along, selects, synthetizes or, physiologically speaking, integrates those trains of ideas which help most effectually to reach the destination, or, in other words, are especially fit for the purpose in hand.
This selective will-activity of the highest nerve-systems, given in the will-effort of selection, forms the very nucleus of man's rational life.
These superior selective "choice and will centers," localized by Ferrier, Wundt, Bianchi and others, in the frontal lobes, and by others in the upper layers of the cortex, on account of their selective and inhibitory functions, may be characterized as selective and inhibitory centers par excellence.
Man's nerve organization may thus be classified into two main systems: I. the inferior, including the reflex, the instinctive, the automatic centres; and II. the superior, the controlling, selective, and inhibitory brain-centres of the cortex. Parallel to the double systems of nerve-centres, we also have a double mental activity, or double-consciousness as it is sometimes called, the inferior, the organic, the instinctive, the automatic, the reflex consciousness, or briefly termed the subconsciousness; and the superior, the choosing, the willing, the critical, the will-consciousness. This controlling will-consciousness may also be characterized as the guardian-consciousness of the species and of the individual.
From an evolutionary, or teleological standpoint, we can well realize the biological function or importance of this guardian-consciousness. The external world bombards the living organism with
