Thomas Aquinas, Disputed Questions on Truth (De Veritate)

1. On Psalms (52:2), "They are corrupted and become abominable," the Gloss has: "Corrupted, that is, deprived of all light of reason." But the light of synderesis is the light of reason. Therefore, in some men synderesis is extinguished.

2. Heretics sometimes have no remorse of conscience for their infidelity. But infidelity is a sin. Accordingly, since the function of synderesis is to protest against sin, it seems that it is extinguished in them.

3. According to the Philosopher, one who has a habit of vice loses the principles of action. But principles of action belong to synderesis. Therefore, in everyone who has the habit of some vice synderesis is extinguished.

4. Proverbs (18:3) says: "The wicked man when he is come into the depth of sins, contemneth." When this happens, "synderesis does not hold its ground," as Jerome says. Therefore, in some men it is extinguished.

5. Every inclination to evil is taken away from the blessed. Conversely, therefore, every inclination to good is taken away from the damned. But synderesis inclines to good. Therefore, it is extinguished in them.

To the Contrary:

1'. Isaias (66:24) says: "Their worm shall not die." According to Augustine, this refers to the worm of conscience, which is remorse of conscience. But remorse of conscience is caused by synderesis protesting against evil. Therefore, synderesis is not destroyed.

2'. Despair, which is a sin against the Holy Spirit, is in the lowest depths of sin. But, even in those who despair, "synderesis is not extinguished," as is plain from Jerome, who says of synderesis: "Not even in Cain was it suppressed." Nevertheless, it is clear that he despaired, for he said: "My iniquity is greater than that I may deserve pardon" (Genesis 4:13). We conclude as before.

REPLY:

That synderesis is extinguished can be understood in two ways. In one, it is considered in so far as it is an habitual light, and in this sense it is impossible for synderesis to be extinguished, just as it is impossible for the soul of a man to be deprived of the light of the agent intellect, through which first principles in speculative and practical matters are made known to us. For this light belongs to the nature of the soul, since by reason of this the soul is intellectual. In Psalms (4:7) it is said of this: "The light of thy countenance, O Lord, is signed upon us," so that it shows good things to us. For this was the answer to the question: "Many say: Who sheweth us good things?" (Psalms 4:6).

In the other way, in so far as it is an act, it can be extinguished in two ways. In one, the act of synderesis is said to be extinguished inasmuch as it is completely interfered with. This happens in those who do not have the use of free choice or of reason because of an impediment due to an injury to the bodily organs from which our reason needs help. In the other way, the act of synderesis is deflected toward the contrary of synderesis. It is impossible for the universal judgment of synderesis to be destroyed in this way, but in a particular activity it is destroyed whenever one sins in choice. For the force of concupiscence, or of another passion, so absorbs reason that in choice the universal judgment of synderesis is not applied to the particular act. But this does not destroy synderesis altogether, but only in some respect. Hence, absolutely speaking, we concede that synderesis is never destroyed.

Answers to Difficulties:

1. Some sinners are said to be deprived of all light of reason in the act of choice, in which reason errs because it is engrossed by some passion, or oppressed by some habit so that it does not follow the light of synderesis in making its choice.

2. In heretics their conscience does not reprove their infidelity by reason of the error in their higher reason, because of which the judgment of synderesis is not applied to this particular case. For the universal judgment of synderesis remains in them, since they judge it to be evil not to believe what God has said. But they err in higher reason, because they do not believe that God has said this.

3. One who has the habit of some vice does indeed lose the principles of activity, not as universal principles, but in their application to some particular case, in so far as through some vicious habit his reason is stifled in order to keep it from applying the universal judgment to its particular activity when making its choice. In this way, also, the wicked man who falls into the depths of sin is said to have contempt.

4. The solution to the fourth difficulty is clear from the answer to the third.

5. Evil is not part of a nature; therefore, there is nothing to prevent the removal of the inclination to evil from the blessed. But good and the inclination thereto result from the nature itself; hence, as long as the nature remains, the inclination to good cannot be taken even from the damned.