failure in solving the problems of mental philosophy be expected from a system, even though that system were sustained by surpassing intellectual force, that ignored the instrument, brain, by which the result, mind, is evolved? What success could be expected from an inquiry into the mechanism of respiration, from which all consideration of the structure, dynamics, and chemistry of the breathing-organs was purposely excluded? Conceive a man proceeding to investigate the respiratory process who had never seen a lung! Should we consider him perfectly sane? How ineffably curious, then, if not ludicrous, does it seem to find Bain announcing, with in some sort the tone of a man who has stumbled on a happy discovery, that it would be worth the while of metaphysicians to learn something of nerves—we presume, impliedly, something of brain also! Still this niggard dole of acknowledgment places the donor at all events in advance of J. S. Mill, who to the very close of his career contemptuously and obtrusively rejected cerebral physiology as a guide, of even the most subordinate value, in the study of mind. Why, the solitary discovery of the connection of aphasia with a special spot in a special gyrus of a special hemisphere of the brain, taken in conjunction with the corollaries logically deducible from that connection, seems a far weightier offering toward the elucidation of the actual mechanism of mind—of the conditions under which Nature works—than all the transcendental guesswork furnished by the toil of metaphysicians from Plato to Schopenhauer.
Nevertheless, the conspicuous failure of purely introspective philosophy, unaided by objective investigation, to establish its special psychic doctrines, does not, on the other hand, disprove the possible independent existence of soul as one of the factors of mind. Such existence may be, or may not be, a reality, for anything that metaphysics show or do not show. The failure of transcendentalism, admitted even by Kant, simply proves that in wisdom which is not of pure and unaided metaphysics lies such lingering hope, as an enthusiast may cling to, of substantiating the reality and the nature of the soul's existence and practical activity. Nor does the failure signify (whatever may be its import as to the efficiency of transcendentalism) that introspection must not be allowed to play a large though far from the solitary part in the attempt to elucidate the nature of mental operations. To reject the help of introspection in analyzing the phenomena of mind would be as illogical, nay fatuous, on the part of the physiologist as the negation of the utility of all objective aid by the bulk of metaphysicians. But in point of fact such rejection is a sheer impossibility, for we can not cogitate without examining consciousness, and when we do this we introspect. Besides, there are facts of mental operation, and laws regulating these facts, which lie without the pale of physiology as an objective factor, facts and laws which can only be even guessed at by the analysis of self -consciousness. The results of
