in doing good, whereas he helped him to sin. In such a case the
repayment due to him is not that he should be helped to commit a sin,
because this would be repaying not good but evil, and this is
contrary to gratitude.

Reply Obj. 2: No man is excused from ingratitude through inability to
repay, for the very reason that the mere will suffices for the
repayment of the debt of gratitude, as stated above (Q. 106, A. 6, ad
1).

Forgetfulness of a favor received amounts to ingratitude, not indeed
the forgetfulness that arises from a natural defect, that is not
subject to the will, but that which arises from negligence. For, as
Seneca observes (De Benef. iii), "when forgetfulness of favors lays
hold of a man, he has apparently given little thought to their
repayment."

Reply Obj. 3: The debt of gratitude flows from the debt of love, and
from the latter no man should wish to be free. Hence that anyone
should owe this debt unwillingly seems to arise from lack of love for
his benefactor.
_______________________

SECOND ARTICLE [II-II, Q. 107, Art. 2]

Whether Ingratitude Is a Special Sin?

Objection 1: It seems that ingratitude is not a special sin. For
whoever sins acts against God his sovereign benefactor. But this
pertains to ingratitude. Therefore ingratitude is not a special sin.

Obj. 2: Further, no special sin is contained under different kinds of
sin. But one can be ungrateful by committing different kinds of sin,
for instance by calumny, theft, or something similar committed
against a benefactor. Therefore ingratitude is not a special sin.

Obj. 3: Further, Seneca writes (De Benef. iii): "It is ungrateful to
take no notice of a kindness, it is ungrateful not to repay one, but
it is the height of ingratitude to forget it." Now these do not seem
to belong to the same species of sin. Therefore ingratitude is not a
special sin.

_On the contrary,_ Ingratitude is opposed to gratitude or
thankfulness, which is a special virtue. Therefore it is a special
sin.

_I answer that,_ Every vice is denominated from a deficiency of
virtue, because deficiency is more opposed to virtue: thus
illiberality is more opposed to liberality than prodigality is. Now a
vice may be opposed to the virtue of gratitude by way of excess, for
instance if one were to show gratitude for things for which gratitude
is not due, or sooner than it is due, as stated above (Q. 106, A. 4).
But still more opposed to gratitude is the vice denoting d