Thomas Aquinas

“ Wherefore if color be offered to the sight, it moves the sight necessarily: unless one turns one's eyes away; which belongs to the exercise of the act. But if the sight were confronted with something not in all respects colored actually, but only so in some respects, and in other respects not, the sight would not of necessity see such an object: for it might look at that part of the object which is not actually colored, and thus it would not see it. Now just as the actually colored is the object of sight, so is good the object of the will. ”

“ The will is distinguished from nature as one kind of cause from another; for some things happen naturally and some are done voluntarily. There is, however, another manner of causing that is proper to the will, which is mistress of its act, besides the manner proper to nature, which is determinate to one thing. But since the will is founded on some nature, it is necessary that the movement proper to nature be shared by the will, to some extent: just as what belongs to a previous cause is shared by a subsequent cause. ”

“ The sufficient mover of a power is none but that object that in every respect presents the aspect of the mover of that power. If, on the other hand, it is lacking in any respect, it will not move of necessity, as stated above. ”

“ The Divine will extends not only to the doing of something by the thing which He moves, but also to its being done in a way which is fitting to the nature of that thing. And therefore it would be more repugnant to the Divine motion, for the will to be moved of necessity, which is not fitting to its nature; than for it to be moved freely, which is becoming to its nature. ”

“ Whereas any other particular goods, in so far as they are lacking in some good, can be regarded as non-goods: and from this point of view, they can be set aside or approved by the will, which can tend to one and the same thing from various points of view. ”

“ For it is not only things pertaining to the will that the will desires, but also that which pertains to each power, and to the entire man. Wherefore man wills naturally not only the object of the will, but also other things that are appropriate to the other powers; such as the knowledge of truth, which befits the intellect ”

“ And in respect of this, man can either repel the passion entirely, or at least hold himself in check so as not to be led away by the passion. For when thus disposed, since man is variously disposed according to the various parts of the soul, a thing appears to him otherwise according to his reason, than it does according to a passion. ”

“ The will is moved not only by the universal good apprehended by the reason, but also by good apprehended by sense. Wherefore he can be moved to some particular good independently of a passion of the sensitive appetite. For we will and do many things without passion, and through choice alone; as is most evident in those cases wherein reason resists passion.
Art. 4 - Whether the will is moved of necessity by the exterior mover which is God? Objection 1: It would seem that the will is moved of necessity by God. For every agent that cannot be resisted moves of necessity. ”

“ Further, a universal cause is not applied to a particular effect, except by means of a particular cause: wherefore the universal reason does not move save by means of a particular estimation, as stated in De Anima iii, 11. But as the universal reason is to the particular estimation, so is the will to the sensitive appetite. Therefore the will is not moved to will something particular, except through the sensitive appetite. Therefore, if the sensitive appetite happen to be disposed to something, by reason of a passion, the will cannot be moved in a contrary sense. ”

“ Since, therefore, the will is an active principle, not determinate to one thing, but having an indifferent relation to many things, God so moves it, that He does not determine it of necessity to one thing, but its movement remains contingent and not necessary, except in those things to which it is moved naturally. ”

“ Because in every thing, being itself, which is from nature, precedes volition, which is from the will. And hence it is that the will wills something naturally.
Reply to Objection 2: In the case of natural things, that which is natural, as a result of the form only, is always in them actually, as heat is in fire. But that which is natural as a result of matter, is not always in them actually, but sometimes only in potentiality: because form is act, whereas matter is potentiality. Now movement is "the act of that which is in potentiality" (Aristotle, Phys. iii, 1) . ”

“ To every nature there is one thing corresponding, proportionate, however, to that nature. For to nature considered as a genus, there corresponds something one generically; and to nature as species there corresponds something one specifically ”