hide one's thoughts by artifice, to
conceal one's meaning by words, to represent error as truth, to make
out the truth to be false," and further on he adds: "This prudence is
acquired by the young, it is learnt at a price by children." Now the
above things seem to belong to craftiness. Therefore craftiness is not
distinct from carnal or worldly prudence, and consequently it seems
not to be a special sin.

_On the contrary,_ The Apostle says (2 Cor. 4:2): "We renounce the
hidden things of dishonesty, not walking in craftiness, nor
adulterating the word of God." Therefore craftiness is a sin.

_I answer that,_ Prudence is _right reason applied to action,_ just
as science is _right reason applied to knowledge._ In speculative
matters one may sin against rectitude of knowledge in two ways: in
one way when the reason is led to a false conclusion that appears to
be true; in another way when the reason proceeds from false premises,
that appear to be true, either to a true or to a false conclusion.
Even so a sin may be against prudence, through having some
resemblance thereto, in two ways. First, when the purpose of the
reason is directed to an end which is good not in truth but in
appearance, and this pertains to prudence of the flesh; secondly,
when, in order to obtain a certain end, whether good or evil, a man
uses means that are not true but fictitious and counterfeit, and this
belongs to the sin of craftiness. This is consequently a sin opposed
to prudence, and distinct from prudence of the flesh.

Reply Obj. 1: As Augustine observes (Contra Julian. iv, 3) just as
prudence is sometimes improperly taken in a bad sense, so is
craftiness sometimes taken in a good sense, and this on account of
their mutual resemblance. Properly speaking, however, craftiness is
taken in a bad sense, as the Philosopher states in _Ethic._ vi, 12.

Reply Obj. 2: Craftiness can take counsel both for a good end and for
an evil end: nor should a good end be pursued by means that are false
and counterfeit but by such as are true. Hence craftiness is a sin if
it be directed to a good end.

Reply Obj. 3: Under "worldly prudence" Gregory included everything
that can pertain to false prudence, so that it comprises craftiness
also.
_______________________

FOURTH ARTICLE [II-II, Q. 55, Art. 4]

Whether Guile Is a Sin Pertaining to Craftiness?

Objection 1: It would seem that guile is not a sin pertaining to
craftiness. For sin, especially mortal