Page:Philosophical Review Volume 1.djvu/394

378 A represents a nervous centre and B the point of stimulus and AB the line of transmission. AC represents the reflex act. The whole series of phenomena occurring between B and C is simply one of mechanical causation, according to our supposition, and inasmuch as volition in the mature subject passes along the same lines of muscular egress, anteceded by some stimulus known either as an impression or a motive, or both, the character of that event seems to be the same as the action from which it is presumably developed. Supposing also that emotions, desires, sensations, and "motives" in general, occupy the same relation to the volition, which they precede, as the stimulus of reflex action, and are also the effect determined solely by an external stimulus, we have action in every respect like the reflexes. We are prepared to admit that a great many actions are so mediated. The immediate response shown by the infant to some sensation or emotion, without deliberating upon any alternative, and the promptness with which a hungry dog is impelled by the sight of food to seize and eat it, and the thousand acts of almost every individual determining the will at the moment of a sensational experience, are phenomena that show an uninterrupted series from the point B to C, in which the initiative is an external influence. There is no choice or deliberation in the reflexes, and none appears in the immediate transition from a sensation or emotion to volition. This may not be incompatible with freedom, but the presumption, at least, from the order of sequence and its invariability is that the cause is the original stimulus, and not the free impulse of the mind. If then there exists anything to interrupt the development of impulse from B to C so as to present an originating agency from within, and which also renders deliberation possible, we may find the whole case modified. In Figure 1 the reflex arc represents a peripheral receiving point and a motor centre. In the following Figure 2 the illustration is more complex, involving sensory and ideational centres. D represents an