§5. It is, however, of obvious practical importance to ascertain how far the power of the will (whether metaphysically free or not) actually extends: for this defines the range within which ethical judgments are in the strictest sense applicable. This inquiry is quite independent of the question of metaphysical freedom; we might state it in Determinist terms as an inquiry into the range of effects which it would be possible to cause by human volition, provided that adequate motives are not wanting. These effects seem to be mainly of three kinds: first, changes in the external world consequent upon muscular contractions; secondly, changes in the train of ideas and feelings that constitutes our conscious life; and thirdly, changes in the tendencies to act hereafter in certain ways under certain circumstances.
I. The most obvious and prominent part of the sphere of volitional causation is constituted by such events as can be produced by muscular contractions. As regards these, it is sometimes said that it is properly the muscular contraction that we will, and not the more remote effects; for these require the concurrence of other causes, and therefore we can never be absolutely certain that they will follow. But no more is it certain, strictly speaking, that the muscular contraction will follow, since our limb may be paralysed, etc. The immediate consequent of the volition is some molecular change in the motor nerves. Since, however, we are not conscious in willing of our motor nerves and their changes, nor indeed commonly of the muscular contractions that follow them,---it seems a misuse of terms to describe either as the normal `object' of the mind in willing: since it is almost always some more remote effect which we consciously will and intend. Still of almost all effects of our will on the external world some contraction of our muscles is an indispensable antecedent; and when that is over our part in the causation is completed.
II. We can control to some extent our thoughts and feelings. It would seem, indeed, that an important part of what we commonly call `control of feeling' comes under the head just discussed. Our control over our muscles enables us to keep down the expression of the feeling and to resist its promptings to action: and as the giving free vent to a feeling tends, generally speaking, to sustain and prolong it, this muscular control amounts to a certain power over the emotion. But there is not the same connexion between our muscular system and our thoughts: and yet experience shows that most men (though some, no doubt, much more than others) can voluntarily determine the direction of their thoughts, and pursue at will a given line of meditation. In such cases, what is effected by the effort of will seems to be the concentration of our consciousness on a part of its content, so that this part grows more vivid and clear, while the rest tends to become obscure and ultimately to vanish. Frequently this voluntary exertion is only needed to initiate a train of ideas, which is afterwards continued without effort: as in recalling a series of past events or going through a familiar train of reasoning. By such concentration we can free ourselves of many thoughts and feelings upon which we do not wish to dwell: but our power to do this is very limited, and if the feeling be strong and its cause persistent, it requires a very unusual effort of will to banish it thus.
III. The effect of volition, however, to which I especially wish to direct the reader's attention is the alteration in men's tendencies to future action which must be assumed to be a consequence of general resolutions as to future conduct, so far as they are effective. Even a resolution to do a particular act---if it is worth while to make it, as experience shows it to be---must be supposed to produce a change of this kind in the person who makes it: it must somehow modify his present tendencies to act in a certain way on a foreseen future occasion. But it is in making general resolutions for future conduct that it is of most practical importance for us to know what is within the power of the will. Let us take an example. A man has been in the habit of drinking too much brandy nightly: one morning he resolves that he will do so no more. In making this resolve he acts under the belief that by a present volition he can so far alter his habitual tendency to indulgence in brandy, that some hours hence he will resist the full force of his habitual craving for the stimulant. Now whether this belief is well or ill founded is a different question from that usually discussed between Determinists and Libertarians: at the same time the two questions are liable to be confused. It is sometimes vaguely thought that a belief in Free Will requires us to maintain that at any moment we can alter our habits to any extent by a sufficiently strong exertion. And no doubt most commonly when we make such efforts, we believe at the moment that they will be completely effectual: we will to do something hours or days hence with the same confidence with which we will to do something immediately. But on reflection, no one, I think, will maintain that in such cases the future act appears to be in his power in the same sense as a choice of alternatives that takes effect immediately. Not only does continual experience show us that such resolutions as to the future have a limited and too frequently an inadequate effect: but the common belief is really inconsistent with the very doctrine of Free Will that is thought to justify it: for if by a present volition I can fully determine an action that is to take place some hours hence, when the time comes to do that act I shall find myself no longer free. We must therefore accept the conclusion that each such resolve has only a limited effect: and that we cannot know when making it how far this effect will exhibit itself in the performance of the act resolved upon. At the same time it can hardly be denied that such resolves sometimes succeed in breaking old habits: and even when they fail to do this, they often substitute a painful struggle for smooth and easy indulgence. Hence it is reasonable to suppose that they always produce some effect in this direction; whether they operate by causing new motives to present themselves on the side of reason, when the time of inner conflict arrives; or whether they directly weaken the impulsive force of habit in the same manner as an actual breach of custom does, though in an inferior degree.
If this account of the range of volition be accepted, it will, I trust, dispel any lingering doubts which the argument of the preceding section, as to the practical unimportance of the Free Will controversy, may have left in the reader's mind. For it may have been vaguely thought that while on the Determinist theory it would be wrong, in certain cases, to perform a single act of virtue if we had no ground for believing that we should hereafter duly follow it up; on the assumption of Freedom we should boldly do always what would be best if consistently followed up, being conscious that such consistency is in our power. But the supposed difference vanishes, if it be admitted that by any effort of resolution at the present moment we can only produce a certain limited effect upon our tendencies to action at some future time, and that immediate consciousness cannot tell us that this effect will be adequate to the occasion, nor indeed how great it will really prove to be. For the most extreme Libertarian must then allow that before pledging ourselves to any future course of action we ought to estimate carefully, from our experience of ourselves and general knowledge of human nature, what the probability is of our keeping present resolutions in the circumstances in which we are likely to be placed. It is no doubt morally most important that we should not tranquilly acquiesce in any weakness or want of self-control: but the fact remains that such weakness is not curable by a single volition: and whatever we can do towards curing it by any effort of will-at any moment, is as clearly enjoined by reason on the Determinist theory as it is on the Libertarian. On neither theory is it reasonable that we should deceive ourselves as to the extent of our weakness, or ignore it in the forecast of our conduct, or suppose it more easily remediable than it really is.