hether these vices arise from sins of the flesh?
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FIRST ARTICLE [II-II, Q. 15, Art. 1]

Whether Blindness of Mind Is a Sin?

Objection 1: It would seem that blindness of mind is not a sin.
Because, seemingly, that which excuses from sin is not itself a sin.
Now blindness of mind excuses from sin; for it is written (John
9:41): "If you were blind, you should not have sin." Therefore
blindness of mind is not a sin.

Obj. 2: Further, punishment differs from guilt. But blindness of mind
is a punishment as appears from Isa. 6:10, "Blind the heart of this
people," for, since it is an evil, it could not be from God, were it
not a punishment. Therefore blindness of mind is not a sin.

Obj. 3: Further, every sin is voluntary, according to Augustine (De
Vera Relig. xiv). Now blindness of mind is not voluntary, since, as
Augustine says (Confess. x), "all love to know the resplendent
truth," and as we read in Eccles. 11:7, "the light is sweet and it is
delightful for the eyes to see the sun." Therefore blindness of mind
is not a sin.

_On the contrary,_ Gregory (Moral. xxxi, 45) reckons blindness of
mind among the vices arising from lust.

_I answer that,_ Just as bodily blindness is the privation of the
principle of bodily sight, so blindness of mind is the privation of
the principle of mental or intellectual sight. Now this has a
threefold principle. One is the light of natural reason, which light,
since it pertains to the species of the rational soul, is never
forfeit from the soul, and yet, at times, it is prevented from
exercising its proper act, through being hindered by the lower powers
which the human intellect needs in order to understand, for instance
in the case of imbeciles and madmen, as stated in the First Part (Q.
84, AA. 7, 8).

Another principle of intellectual sight is a certain habitual light
superadded to the natural light of reason, which light is sometimes
forfeit from the soul. This privation is blindness, and is a
punishment, in so far as the privation of the light of grace is a
punishment. Hence it is written concerning some (Wis. 2:21): "Their
own malice blinded them."

A third principle of intellectual sight is an intelligible principle,
through which a man understands other things; to which principle a
man may attend or not attend. That he does not attend thereto happens
in two ways. Sometimes it is due to the fact that a man's will is
deliberately turned away from th