ophers
made any true statements, we must claim them for our own use, as from
unjust possessors." Therefore curiosity about intellective knowledge
cannot be sinful.

_On the contrary,_ Jerome [*Comment. in Ep. ad Ephes. iv, 17] says:
"Is it not evident that a man who day and night wrestles with the
dialectic art, the student of natural science whose gaze pierces the
heavens, walks in vanity of understanding and darkness of mind?" Now
vanity of understanding and darkness of mind are sinful. Therefore
curiosity about intellective sciences may be sinful.

_I answer that,_ As stated above (Q. 166, A. 2, ad 2) studiousness is
directly, not about knowledge itself, but about the desire and study
in the pursuit of knowledge. Now we must judge differently of the
knowledge itself of truth, and of the desire and study in the pursuit
of the knowledge of truth. For the knowledge of truth, strictly
speaking, is good, but it may be evil accidentally, by reason of some
result, either because one takes pride in knowing the truth,
according to 1 Cor. 8:1, "Knowledge puffeth up," or because one uses
the knowledge of truth in order to sin.

On the other hand, the desire or study in pursuing the knowledge of
truth may be right or wrong. First, when one tends by his study to
the knowledge of truth as having evil accidentally annexed to it, for
instance those who study to know the truth that they may take pride
in their knowledge. Hence Augustine says (De Morib. Eccl. 21): "Some
there are who forsaking virtue, and ignorant of what God is, and of
the majesty of that nature which ever remains the same, imagine they
are doing something great, if with surpassing curiosity and keenness
they explore the whole mass of this body which we call the world. So
great a pride is thus begotten, that one would think they dwelt in
the very heavens about which they argue." In like manner, those who
study to learn something in order to sin are engaged in a sinful
study, according to the saying of Jer. 9:5, "They have taught their
tongue to speak lies, they have labored to commit iniquity."

Secondly, there may be sin by reason of the appetite or study
directed to the learning of truth being itself inordinate; and this
in four ways. First, when a man is withdrawn by a less profitable
study from a study that is an obligation incumbent on him; hence
Jerome says [*Epist. xxi ad Damas]: "We see priests forsaking the
gospels and the prophets, reading stage-plays,