many if not most of the assured conclusions of the physical sciences.
As regards the first of these two main contentions, it must suffice here to point out the main difficulties in which a Objections to materialism. determinist and especially materialist account of the relation between consciousness and the organic processes which accompany it appears to be involved. The arguments of thorough-going materialism can in most cases be met with a direct negative. No kind of evidence can be adduced sufficient to prove that consciousness is a secretion of the brain, an effect or even a consequent of material processes or modes of motion. No direct causal relationship between a molecular movement and a state of consciousness has ever been established. No physiologist has ever claimed the power to prophesy with any approach to accuracy the future mental states of any individual from an examination of his brain. And, though some kind of correspondence between the physical and conscious series of states has been observed and is commonly taken for granted in a number of instances, proof that entire correspondence exists is still wanting, and the precise kind of correspondence is left undetermined. Nevertheless, the belief that material processes must be held sufficient to account for material changes in the human organism as in all other regions of the material world, can be held quite independently of any particular theory as to the relation between mind and body, and in nwny of its forms is equally destructive of a belief in the freedom of the will. It is a belief, too, which is increasingly prevalent in modern science. The theory of psychophysical parallelism involves no doubt in the minds of the majority of its upholders the further assumption of some unity underlying both the physical and psychical series which may one day be discovered to be susceptible of scientific expression and interpretation. Certainly without some such assumption the hypothesis of an exact correspondence between the series described as parallel becomes, as Professor Ward has shown, unmeaning. And many scientific thinkers, while professing allegiance to a theory which insists upon the independence of each parallel series, in reality tacitly assume the superior importance if not the controlling force of the physical over the psychical terms. But a mere insistence upon the complete independence of the physical series coupled with the belief that its changes are wholly explicable as modes of motion, i.e. that the study of molecular physics is competent to explain all the phenomena of life and organic movements, is sufficient to eliminate the possibility of spontaneity and free origination from the universe. For if consciousness be looked upon as simply an epiphenomenon, an unaccountable appearance accompanying the succession of material changes, the possibility either of active interference by human volition at any point within the physical series or of any controlling or directing efficacy of consciousness over the whole set of material changes which accompany its activity becomes unthinkable. There are, nevertheless, serious difficulties involved in the supposition that the changes in the brain with which physiology and the biological sciences deal can be satisfactorily explained by the mechanical and mathematical conceptions common to all these sciences, or, indeed, that any of these organic changes is susceptible in the last resort of explanation derived from purely material premises. The phenomena of life and growth and assimilation have not been satisfactorily explained as mechanical modes of motion, and the fact that identical cerebral movements have not been discovered to recur makes scientific and accurate prediction of future cerebral changes an impossibility. But more convincing than most of the philosophical arguments by which the theories of psychophysical parallelism have been assailed is the fact that it runs counter to the plain evidence of the ordinary consciousness. No matter to what extent the unphilosophical thinker may be under the influence of materialistic presuppositions, he always recoils from the conclusion that the facts of his mental life have no influence upon his physical movements. Meaning, design and purpose are to him terms far more explanatory of his movements in the outer world than the mechanical and mathematical equivalents to which his actions will ultimately be reduced if the sciences should achieve their avowed purpose. To regard himself as a conscious automaton he can never be persuaded. Further, he finds in the series of antecedents and consequents capable of mathematical and spatial determination, which certain men of science present to him as their final account of his physical and psychical history, no real explanation of the facts: he is far more inclined to look for an explanation of the efficacy of causal changes in the categories of will and purpose for which they are a substitution.
Nor, finally, is the last defensive position of scientific determinism—the theory, namely, that the freedom of the will is incompatible with the doctrine of the conservation of energy—to be accepted without question. That doctrine, if it is to possess cogency as a proof of the impossibility of the libertarian position, must assume that the amount of energy sufficient to account for physical and psychical changes is constant and invariable in quantity, an assumption which no scientific investigator is competent to prove. A regulative principle which may possess great value when applied and confined to the comparatively abstract material of the mathematical and quasi-mathematical sciences is highly dangerous if extended to the investigation of living bodies. “In its present form, and since the development of the mechanical theory of heat, the principle of the conservation of energy certainly seems to apply to the whole range of physico-chemical phenomena. But no one can tell whether the study of physiological phenomena in general, and of nervous phenomena in particular, will not reveal to us, besides the vis viva or kinetic energy of which Leibnitz spoke, and the potential energy which was a later and necessary adjunct, some new kind of energy which may differ from the other two by rebelling against calculation” (Bergson, Time and Free Will, Eng. trans. by F. L. Pogson, pp. 151, 152).
It is, however, from the development of the scientific study of psychology more than from any other region of thought Modern psychology. that light has been thrown upon the problem of freedom. The determinist presuppositions of psychology (determinist because they involve the application of the causal conceptions of modern science to mental phenomena) have in many instances in no way retarded the utilization of new information concerning mental processes in order to prove the reality of freedom. Bergson is perhaps the most notable instance of a philosopher fully conversant with psychological studies and methods who remains a convinced libertarian. But the contribution made by psychology to the solution of the problem has taken the form not so much of a direct reinforcement of the arguments of either of the opponent systems, as of a searching criticism of the false assumptions concerning conative processes and the phenomena of choice common alike to determinists and libertarians. It has already been pointed out that the problem as it presented itself to utilitarian philosophers could lead only to a false solution, depending as it did upon a wholly fictitious theory as to the nature of desire. There are still many traces to be found in modern psychology of a similar unreal identification of desire with will. But, nevertheless, the new light thrown upon the unity of the self and the more careful and accurate scrutiny made by recent psychologists of the phenomena of decision have rendered it no longer possible either for determinists to deny the fact of choice (whatever be their theory as to its nature) or for libertarians to regard the self or the will as isolated from and unaffected by other mental constituents and antecedents, and hence, by an appeal to wholly fictitious entities, to prove the truth of freedom. The self or the will can no longer be looked upon as possessing a kind of imperium in imperio, “this way and that dividing the swift mind.” And if freedom of choice be a possibility at all, it must in future be regarded as the prerogative of a man's whole personality, exhibited continuously throughout the development of his character, displayed to some extent in all conscious conative processes, though especially apparent in crises necessitating deliberate and serious purpose. The mistake of earlier advocates of determinism lay in the
