---
title: "Summa Theologica, First Half"
author: "Thomas Aquinas"
translator: "Fathers of the English Dominican Province"
languages: [en]
shelf: "Medieval"
section: 657 of 1210
url: https://scriptura.si/works/thomas-aquinas-summa-theologica-first-half/657/
cite: "Thomas Aquinas, tr. Fathers of the English Dominican Province, Summa Theologica, First Half, section 657. Scriptura (scriptura.si), https://scriptura.si/works/thomas-aquinas-summa-theologica-first-half/657/"
---

# Summa Theologica, First Half

*Thomas Aquinas, tr. Fathers of the English Dominican Province*

God and creation, human action, law and grace, then faith, hope, charity and justice.

## 657. I–II · Q. 74, Art. 2: Whether the will alone is the subject of sin?

Source: https://scriptura.si/works/thomas-aquinas-summa-theologica-first-half/657/ · cite a paragraph as https://scriptura.si/works/thomas-aquinas-summa-theologica-first-half/657/#p-N

[¶0] Whether the will alone is the subject of sin?

[¶1] Objection 1: It would seem that the will alone is the subject of sin. For Augustine says (De Duabus Anim. x, 10) that "no one sins except by the will." Now the subject of sin is the power by which we sin. Therefore the will alone is the subject of sin.

[¶2] Objection 2: Further, sin is an evil contrary to reason. Now good and evil pertaining to reason are the object of the will alone. Therefore the will alone is the subject of sin.

[¶3] Objection 3: Further, every sin is a voluntary act, because, as Augustine states (De Lib. Arb. iii, 18) [*Cf. De Vera Relig. xiv.], "so true is it that every sin is voluntary, that unless it be voluntary, it is no sin at all." Now the acts of the other powers are not voluntary, except in so far as those powers are moved by the will; nor does this suffice for them to be the subject of sin, because then even the external members of the body, which are moved by the will, would be a subject of sin; which is clearly untrue. Therefore the will alone is the subject of sin.

[¶4] On the contrary, Sin is contrary to virtue: and contraries are about one same thing. But the other powers of the soul, besides the will, are the subject of virtues, as stated above (Q 56). Therefore the will is not the only subject of sin.

[¶5] I answer that, As was shown above (A 1), whatever is the a principle of a voluntary act is a subject of sin. Now voluntary acts are not only those which are elicited by the will, but also those which are commanded by the will, as we stated above (Q 6, A 4) in treating of voluntariness. Therefore not only the will can be a subject of sin, but also all those powers which can be moved to their acts, or restrained from their acts, by the will; and these same powers are the subjects of good and evil moral habits, because act and habit belong to the same subject.

[¶6] Reply to Objection 1: We do not sin except by the will as first mover; but we sin by the other powers as moved by the will.

[¶7] Reply to Objection 2: Good and evil pertain to the will as its proper objects; but the other powers have certain determinate goods and evils, by reason of which they can be the subject of virtue, vice, and sin, in so far as they partake of will and reason.

[¶8] Reply to Objection 3: The members of the body are not principles but merely organs of action: wherefore they are compared to the soul which moves them, as a slave who is moved but moves no other. On the other hand, the internal appetitive powers are compared to reason as free agents, because they both act and are acted upon, as is made clear in Polit. i, 3. Moreover, the acts of the external members are actions that pass into external matter, as may be seen in the blow that is inflicted in the sin of murder. Consequently there is no comparison.

### I–II · Q. 74, Art. 3: Whether there can be sin in the sensuality?

[¶10] Whether there can be sin in the sensuality?

[¶11] Objection 1: It would seem that there cannot be sin in the sensuality. For sin is proper to man who is praised or blamed for his actions. Now sensuality is common to us and irrational animals. Therefore sin cannot be in the sensuality.

[¶12] Objection 2: Further, "no man sins in what he cannot avoid," as Augustine states (De Lib. Arb. iii, 18). But man cannot prevent the movement of the sensuality from being inordinate, since "the sensuality ever remains corrupt, so long as we abide in this mortal life; wherefore it is signified by the serpent," as Augustine declares (De Trin. xii, 12,13). Therefore the inordinate movement of the sensuality is not a sin.

[¶13] Objection 3: Further, that which man himself does not do is not imputed to him as a sin. Now "that alone do we seem to do ourselves, which we do with the deliberation of reason," as the Philosopher says (Ethic. ix, 8). Therefore the movement of the sensuality, which is without the deliberation of reason, is not imputed to a man as a sin.

[¶14] On the contrary, It is written (Rom. 7:19): "The good which I will I do not; but the evil which I will not, that I do": which words Augustine explains (Contra Julian. iii, 26; De Verb. Apost. xii, 2,3), as referring to the evil of concupiscence, which is clearly a movement of the sensuality. Therefore there can be sin in the sensuality.

[¶15] I answer that, As stated above (AA 2,3), sin may be found in any power whose act can be voluntary and inordinate, wherein consists the nature of sin. Now it is evident that the act of the sensuality, or sensitive appetite, is naturally inclined to be moved by the will. Wherefore it follows that sin can be in the sensuality.

[¶16] Reply to Objection 1: Although some of the powers of the sensitive part are common to us and irrational animals, nevertheless, in us, they have a certain excellence through being united to the reason; thus we surpass other animals in the sensitive part for as much as we have the powers of cogitation and reminiscence, as stated in the FP, Q 78, A 4. In the same way our sensitive appetite surpasses that of other animals by reason of a certain excellence consisting in its natural aptitude to obey the reason; and in this respect it can be the principle of a voluntary action, and, consequently, the subject of sin.

[¶17] Reply to Objection 2: The continual corruption of the sensuality is to be understood as referring to the "fomes," which is never completely destroyed in this life, since, though the stain of original sin passes, its effect remains. However, this corruption of the "fomes" does not hinder man from using his rational will to check individual inordinate movements, if he be presentient to them, for instance by turning his thoughts to other things. Yet while he is turning his thoughts to something else, an inordinate movement may arise about this also: thus when a man, in order to avoid the movements of concupiscence, turns his thoughts away from carnal pleasures, to the considerations of science, sometimes an unpremeditated movement of vainglory will arise. Consequently, a man cannot avoid all such movements, on account of the aforesaid corruption: but it is enough, for the conditions of a voluntary sin, that he be able to avoid each single one.

[¶18] Reply to Objection 3: Man does not do perfectly himself what he does without the deliberation of reason, since the principal part of man does nothing therein: wherefore such is not perfectly a human act; and consequently it cannot be a perfect act of virtue or of sin, but is something imperfect of that kind. Therefore such movement of the sensuality as forestalls the reason, is a venial sin, which is something imperfect in the genus of sin.