17 But we have reason, one will say, and excel the whole race of dumb animals in understanding. I might believe that this was quite true, if all men lived rationally and wisely, never swerved aside from their duty, abstained from what is forbidden, and withheld themselves from baseness, and if no one through folly and the blindness of ignorance demanded what is injurious and dangerous to himself. I should wish, however, to know what this reason is, through which we are more excellent than all the tribes of animals. Is it because we have made for ourselves houses, by which we can avoid the cold of winter and heat of summer?
What! Do not the other animals show forethought in this respect? Do we not see some build nests as dwellings for themselves in the most convenient situations; others shelter and secure themselves in rocks and lofty crags; others burrow in the ground, and prepare for themselves strongholds and lairs in the pits which they have dug out? But if nature, which gave them life, had chosen to give to them also hands to help them, they too would, without doubt, raise lofty buildings and strike out new works of art. Yet, even in those things which they make with beaks and claws, we see that there are many appearances of reason and wisdom which we men are unable to copy, however much we ponder them, although we have hands to serve us dexterously in every kind of work.
Source: Against the Heathen (New Advent)