Full Idea
Knowledge of truth is not consummated in the sensitive powers of apprehension, for these prepare the way to intellectual knowledge. And therefore in these powers there are none of the virtues by which we know truth; these are in the intellect or reason.
Gist of Idea
Sensation prepares the way for intellectual knowledge, which needs the virtues of reason
Source
Thomas Aquinas (Summa Theologicae [1265], I-II Q56 a5 obj3), quoted by Linda Trinkaus Zagzebski - Virtues of the Mind III 2.2
Book Reference
Zagzebski,Linda: 'Virtues of the Mind' [CUP 1996], p.277
A Reaction
A gem of a quotation for Zagzebski's thesis, that knowledge is defined in terms of the intellectual virtues. The only virtues of perception are in focusing and paying attention to features. Good eyesight is a biological 'virtue', I suppose.