Little, indeed, as we may reflect upon the concatena tion of the processes of cerebral activity, considered as we have here just done, we cannot help arriving at the conclusion, that the voluntary act is in itself nothing but the reaction of the sensibility thrown into agitation ; that it is this that is latent in all voluntary manifesta tions ; and that it is always the sensorium that, under forms the most dissimilar in appearance, reacts and outwardly betrays the inner impressions by which it is excited.
The sensibility is, therefore, always in agitation at the commencement of every voluntary act deve loped. It becomes erect, and excites the opera tions of judgment and reflexion. It is always present, always in vibration, and inspires our words, our acts, our writings and whatever be the power of the motives calculated to attract it away from its inner inclina tions, it follows its preordained desires for what is suitable to it, what pleases it, and shrinks from what is repugnant to it. Every one, as we say, gives his opinion, every one judges according to the manner in which he is impressed, in which he fcels and sensibility, the seeking after what is pleasant to each of us, is, under the name of self-interest, to such an extent the true motive force of all human actions, that we may con stantly declare that it is always this that directs them, like a powerful magnet, and inclines them in this way or that. All this takes place in so unconscious and certain a manner, that in dealing with a crime, or any guilty action, justice, a priori, ascribes responsibility to those who may have had an interest in committing it, by obtaining some profit from its perpetration.
On the other hand, since human sensibility is in itself one of the most mobile of things, and as regards this every one takes his pleasure as he finds it, it results that the manifestations of sensibility will vary infinitely according to individuals, and will sometimes assume paradoxical forms outside of the usual modes of common sensibility. But at bottom, although the sen timents of egotism and personal satisfaction may apparently be masked, the manifestations of the will will always demonstrate their derivation from the same origin. Everyone, as we have said, has his mode of feeling, and just as we see individuals experience satis faction in certain enjoyments which they alone are capable of perceiving, so we find them manifesting these different states of their sensorium in eccentric and extravagant forms. Thus it is that the enthusiasms of
generosity, self-abnegation, even self-sacrifice, are but too often only a disguised manifestation of egotism, a mode of feeling, sui generis, in which we exchange a physical advantage for an emotion of the moral kind.
From the moment, then, in which the personality becomes interested in the realization of such or such a desire, the moment in which, as we say, a resolution has been taken by it, this physiological condition expresses itself in a co-ordinated manner, according to processes which have been acquired by habit and commenced in infancy, and by which we have learnt to make our fellow creatures comprehend by means of a special vocabulary the ideas which germinate in us, the desires that demand satisfaction, and our private aversions.
Henceforward the mental process has made one more step in the intricacies of the cortical substance. It opens up a new path, that of the motor regions proper. A living automatic pianoforte from this moment comes into play, and in various forms ex presses the sensitive keys it is bound to interpret faithfully. It is the instrumental part of our organism that vibrates, and the process, tending more and more to emerge from the plexuses of the cortical substance, becomes concentrated within certain circumscribed limits, in certain psycho-motor regions, and hence, in the form of rapid intermittent stimulations, effects its discharge directly upon the different territories of the corpora striata.
Concatenation of Voluntary Motor Acts.—We have just seen how the voluntary stimulus, conceived in its primary phase of elaboration, in the substance of the plexuses of the sensorium, as a condition of purely psychical vibration, was constituted by a series of multiple elements, all concurring in its genesis ; how it became inevitably united with a previous phenomenon of sensi bility in agitation ; and how, like a living force in evolution, it tended more and more to emerge from the regions where it was conceived.