Summa summae S. Thomae, Tomus II

I say 1°: The voluntary is rightly defined commonly thus: « That which proceeds from an intrinsic principle, with cognition of the end. »

The definition is explained. By intrinsic principle is understood any elicited appetite, rational as well as sensitive; but, because among elicited appetites the will is the more principal, from the principal appetite the voluntary is denominated. Therefore by the first particles the voluntary is distinguished from the violent, whose principle is outside; likewise from what is willed simply, which does not proceed from any influx of will, but is its object and term extrinsically denominated from volition; thus rain is willed by the farmer, but not voluntary to him. By the last particles it is distinguished from natural motion; because, although natural motion is from an intrinsic efficient principle, yet it is not from an intrinsic final principle, or it is not with cognition of the end, as appears in the motions of vegetative things and in the motion of heavy and light bodies toward the center: whence such things are not said to move themselves toward the end, but to be moved by another knowing, by whom there is impressed on them the principle of their motion toward the end. Likewise by these particles are excluded from the reason of voluntary the acts of intellect anticipating the act of will and not commanded by it; because, although they are from an intrinsic efficient principle, they do not suppose cognition of the end from which they are caused.

I say 2°: The voluntary is divided 1° into perfect and imperfect ¹. Perfect is that which proceeds from perfect cognition of the end; imperfect that which proceeds from imperfect cognition of the end. For since two things concur to the voluntary, namely the intrinsic principle and cognition of the end, the proper perfection of the voluntary by which it is distinguished from the natural cannot be sought from the intrinsic principle in which it agrees with the natural. Therefore from cognition of the end alone, by which it is distinguished from the natural.

Hence it follows that the perfect voluntary belongs to rational nature alone, the imperfect to brutes ²; because perfect cognition is had when not only is apprehended the thing which is the end, but also is known the reason of the end and the proportion of means to end; and such cognition, since it is collative and discursive, belongs to intellectual nature alone. But imperfect cognition of the end is that which consists in the mere apprehension of the thing which is the end, without the knowledge of the reason and dignity of the end and the proportion of means to end. And such cognition of the end is found in brutes through sense and natural estimation. Therefore the imperfect voluntary agrees with brutes, the perfect with rational nature alone; yet not with all its acts, but only those which proceed with full cognition and advertence; whence sudden motions, motions of children, of the insane, of the half-asleep, are only imperfectly voluntary.

2° The voluntary is divided into necessary and free. Free is that which proceeds from appetite with an indifferent judgment and power toward the opposite, as in man acting with full advertence concerning created goods. Necessary, that which proceeds from appetite with a judgment determined to one without power toward the opposite, as in brutes and human motions preceding the deliberation of reason.

3° The voluntary is divided into the voluntary in itself and the voluntary in cause. Voluntary in itself is whatever proceeds per se from the will expressly willing it, or every act which per se is intended, elicited, commanded, or positively admitted by the will; as, if you deliberately hate an enemy, you wish to kill, you command killing, you positively consent to one willing to kill. It is called also direct, express, and explicit voluntary.

Voluntary in cause is that which in itself is not immediately intended, elicited, or commanded by the will, but follows nevertheless from something willed per se and in itself, and therefore is reckoned willed in another as in its cause: thus quarrels are voluntary in cause for him who deliberately makes himself drunk, knowing that in drunkenness he quarrels freely everywhere, although elsewhere he detests quarrels. It is called also indirect, imperfect, and interpretative voluntary.

For this voluntary, the indirect one or that in cause, theologians commonly require three conditions. The first is that the effect was foreseen, or ought and could have been foreseen in a human way to follow from such cause; failing this, drunkenness is not indirectly voluntary for him who, ignorant of the force of wine and drinking to satiety, becomes drunk, as happened to Noë. Second, that it can. Third, that he ought to remove this cause and impede this effect; for if by no law am I bound to remove this cause, but on the contrary have just reason for positing it, there is no reason why what follows from it against my intention should be imputed to me, at least morally. Hence disordered motions are not imputed as voluntary to the confessor or surgeon, since these are not bound on that account to omit their ministry, but on the contrary have just cause for exercising it.

But when is anyone bound to omit or remove the cause from which an evil effect follows? A question difficult of solution on account of the diversity of cases occurring; for which are to be seen the things I say in the treatise de Jure et Justitia, dissert. VI, a. 12, in the premises, from which I repeat these few things.

That it may be discerned when the cause ought, or ought not, to be omitted or removed on account of the evil effect to follow from it, whether per se or per accidens, the evil effect must be compared with the good, and at the same time weighed how great is the influx of the cause into the evil effect: so that if the cause influences per se and proximately into the evil effect, and this outweighs the good effect, there is grave obligation of omitting or removing the cause; but none if the good effect outweighs, or at least equals, the evil. By what reason we said that just defense need not be omitted, from which proximately follows the death of the unjust invader, because the life of the innocent outweighs or at least equals the life of the noxious man; nor ought the damnation which the unjust invader incurs be attended to, because this does not follow from the just defense of invasion, but from the malice of the invader, to lay aside which lies in his own hand.

But if the cause influences remotely and lightly into the evil effect, and from it some good effect also follows, although it does not outweigh or equal the evil, there is no obligation of removing the cause, because less reason is required for positing a cause influencing only lightly and remotely into evil, than if it influenced gravely and proximately.

Hence you are not bound to abstain from honest and useful conversation on account of the motions arising from it. But if the cause influencing lightly and remotely be venially evil in itself, or from it no good effect follows, then there will be obligation of removing it, but light and only under venial sin, unless in this and the preceding case there be question of grave damage to a neighbor: because that obligation must be estimated according to the quantity of the influx of the cause; for since the effect is voluntary only in the cause, and is contained lightly and remotely in the cause, it is lightly voluntary in it, and consequently imputable to light fault, and further there is light obligation of removing the cause on account of that effect. Hence you are bound under venial sin to abstain from honest but useless conversation, or from curious reading from which you foresee disordered motions will follow, and this not only by reason of the cause itself, which already is venial in itself, but also by reason of the effect itself. I said, for these last two assertions, « unless the evil effect be grave damage to a neighbor; » for then there would be grave obligation of removing the cause, because charity commands us not only not to cause evil to our neighbor, but also, insofar as we conveniently can, to prevent it.

4° The voluntary is divided into positive and negative ³. The author calls it direct and indirect. The positive or direct voluntary is that which proceeds from the will by real influx, as are all acts elicited or commanded by the will. The negative or indirect voluntary indeed does not proceed from the will by real influx, yet depends upon it, whence it is said to proceed from it negatively, as the omission of Mass in one who, adverting to its approaching celebration, applies himself to study, without saying actually and positively: « I do not will to hear it. »

[5° The voluntary is divided into express and tacit. The express voluntary is that which is declared distinctly by word or sign. The tacit voluntary is that which is not distinctly declared, but is gathered from some fact or omission, according to rule 43 of Law: « Who is silent seems to consent. » Truly in interpreting that voluntary one must proceed cautiously and discreetly, on account of this other rule of Law, which is 44: « He who is silent does not confess, but certainly neither does he seem to deny. » There must be added, therefore, that the former rule be rightly understood: « When he is bound to speak, and can. »]

These are the more common divisions of the voluntary; certain others will occur in what follows.

You will ask whether the perfect voluntary is the same as free.

I answer. negatively. For there is given a voluntary necessary from the perfection of cognition, which is perfectly, and more perfectly, voluntary than free, namely beatific love. For this proceeds from a maximally intrinsic principle, namely from the will loving God with whole heart, whole affection, and endeavor, and is accompanied by most perfect cognition, namely the clear vision of God most perfectly flowing into that love and equaling the whole universality of intellect and will.

You will say. The same argument can be made of that necessary love by which God loves himself and produces the Holy Spirit. For it would be absurd to imagine God loving himself with lesser inclination and more imperfect cognition than creatures, whom he loves freely.