Page:Philosophical Review Volume 3.djvu/294



HE 'new psychology' has raised in an acute form the by no means new question of the relation of mind and body. The answer which some of the first contemporary psychologists give to this question is also by no means new; but, like the question itself, it is an 'old friend with a new face.' The automaton or parallelistic theory is a familiar enough philosophical doctrine, placed in a new scientific setting. Causal inter-action or reciprocal 'influence' of mind and body is denied on the ground that this would contradict the law of the conservation of energy. The influence of mind upon body would mean the creation of energy, as the influence of body upon mind would mean its annihilation; but energy is a constant sum, and can only be transferred and transformed, neither increased nor diminished. Between mind and body, therefore, there can be no 'causal efficacy'; so far as causation is concerned, the mental series and the physical series of events are independent. The connection between the two series is that of mere parallelism or correspondence; the terms in the one series are indicative or symbolical of their correlates in the other series, but the former are neither causes nor effects of the latter. Each series is self-contained; and in particular the body is an automaton, a self-acting machine, which needs not, and brooks not, any interference with its processes by the mind. All physical action is strictly reaction to physical stimulus; the accompanying mental events are not among the conditions or antecedents of the physical consequents, they are mere concomitants or epi-phenomena, outside the causal series altogether. In the words of the late Professor Clifford: "All the evidence that we have goes to show that the physical world gets along entirely by itself. . . . The train of physical facts between the stimulus sent into the eye, or to any one of our senses, and the exertion which follows it; and the train of physical facts which goes on in the brain, even when there