the consideration of
speculative sciences. Therefore it seems that in the consideration of
these sciences, man's final happiness consists.

_On the contrary,_ It is written (Jer. 9:23): "Let not the wise man
glory in his wisdom": and this is said in reference to speculative
sciences. Therefore man's final happiness does not consist in the
consideration of these.

_I answer that,_ As stated above (A. 2, ad 4), man's happiness is
twofold, one perfect, the other imperfect. And by perfect happiness
we are to understand that which attains to the true notion of
happiness; and by imperfect happiness that which does not attain
thereto, but partakes of some particular likeness of happiness. Thus
perfect prudence is in man, with whom is the idea of things to be
done; while imperfect prudence is in certain irrational animals, who
are possessed of certain particular instincts in respect of works
similar to works of prudence.

Accordingly perfect happiness cannot consist essentially in the
consideration of speculative sciences. To prove this, we must observe
that the consideration of a speculative science does not extend
beyond the scope of the principles of that science: since the entire
science is virtually contained in its principles. Now the first
principles of speculative sciences are received through the senses,
as the Philosopher clearly states at the beginning of the
_Metaphysics_ (i, 1), and at the end of the _Posterior Analytics_
(ii, 15). Wherefore the entire consideration of speculative sciences
cannot extend farther than knowledge of sensibles can lead. Now man's
final happiness, which is his final perfection cannot consist in the
knowledge of sensibles. For a thing is not perfected by something
lower, except in so far as the lower partakes of something higher.
Now it is evident that the form of a stone or of any sensible, is
lower than man. Consequently the intellect is not perfected by the
form of a stone, as such, but inasmuch as it partakes of a certain
likeness to that which is above the human intellect, viz. the
intelligible light, or something of the kind. Now whatever is by
something else is reduced to that which is of itself. Therefore man's
final perfection must needs be through knowledge of something above
the human intellect. But it has been shown (I, Q. 88, A. 2), that man
cannot acquire through sensibles, the knowledge of separate
substances, which are above the human intellect. Consequently it
follow