Obj. 3: Further, such as a thing is, such does it make a thing to be. But the object of the will is good, by reason of the goodness of nature. Therefore it cannot give moral goodness to the will. Therefore the moral goodness of the will does not depend on the object.
On the contrary, the Philosopher says (Ethic. v, 1) that justice is that habit "from which men wish for just things": and accordingly, virtue is a habit from which men wish for good things. But a good will is one which is in accordance with virtue. Therefore the goodness of the will is from the fact that a man wills that which is good.
I answer that, Good and evil are essential differences of the act of the will. Because good and evil of themselves regard the will; just as truth and falsehood regard reason; the act of which is divided essentially by the difference of truth and falsehood, for as much as an opinion is said to be true or false. Consequently good and evil will are acts differing in species. Now the specific difference in acts is according to objects, as stated above (Q. 18, A. 5). Therefore good and evil in the acts of the will is derived properly from the objects.
Reply Obj. 1: The will is not always directed to what is truly good, but sometimes to the apparent good; which has indeed some measure of good, but not of a good that is simply suitable to be desired. Hence it is that the act of the will is not always good, but sometimes evil.
Reply Obj. 2: Although an action can, in a certain way, be man's last end; nevertheless such action is not an act of the will, as stated above (Q. 1, A. 1, ad 2).
Reply Obj. 3: Good is presented to the will as its object by the reason: and in so far as it is in accord with reason, it enters the moral order, and causes moral goodness in the act of the will: because the reason is the principle of human and moral acts, as stated above (Q. 18, A. 5). ________________________
SECOND ARTICLE [I-II, Q. 19, Art. 2]
Whether the goodness of the will depends on the object alone?
Objection 1: It would seem that the goodness of the will does not depend on the object alone. For the end has a closer relationship to the will than to any other power. But the acts of the other powers derive goodness not only from the object but also from the end, as we have shown above (Q. 18, A. 4). Therefore the act also of the will derives goodness not only from the object but also from the end.
Obj. 2: Further, the goodness of an action is derived not only from the object but also from the circumstances, as stated above (Q. 18, A. 3). But according to the diversity of circumstances there may be diversity of goodness and malice in the act of the will: for instance, if a man will, when he ought, where he ought, as much as he ought, and how he ought, or if he will as he ought not. Therefore the goodness of the will depends not only on the object, but also on the circumstances.