And is not reasoning intelligence eclipsed by animals in their provision for atmospheric changes? Do we not see sheep, when winter is approaching, devouring grass with avidity as if to make provision for future scarcity? Do we not also see oxen, long confined in the winter season, recognise the return of spring by a natural sensation, and look to the end of their stables towards the doors, all turning their heads there by common consent? Studious observers have remarked that the hedgehog makes an opening at the two extremities of his hole. If the wind from the north is going to blow he shuts up the aperture which looks towards the north; if the south wind succeeds it the animal passes to the northern door. What lesson do these animals teach man? They not only show us in our Creator a care which extends to all beings, but a certain presentiment of future even in brutes. Then we ought not to attach ourselves to this present life and ought to give all heed to that which is to come. Will you not be industrious for yourself, O man? And will you not lay up in the present age rest in that which is to come, after having seen the example of the ant? The ant during summer collects treasures for winter. Far from giving itself up to idleness, before this season has made it feel its severity, it hastens to work with an invincible zeal until it has abundantly filled its storehouses. Here again, how far it is from being negligent! With what wise foresight it manages so as to keep its provisions as long as possible! With its pincers it cuts the grains in half, for fear lest they should germinate and not serve for its food. If they are damp it dries them; and it does not spread them out in all weathers, but when it feels that the air will keep of a mild temperature. Be sure that you will never see rain fall from the clouds so long as the ant has left the grain out.
What language can attain to the marvels of the Creator? What ear could understand them? And what time would be sufficient to relate them? Let us say, then, with the prophet, “O Lord, how manifold are your works! In wisdom have you made them all.” We shall not be able to say in self-justification, that we have learned useful knowledge in books, since the untaught law of nature makes us choose that which is advantageous to us. Do you know what good you ought to do your neighbour? The good that you expect from him yourself. Do you know what is evil? That which you would not wish another to do to you. Neither botanical researches nor the experience of simples have made animals discover those which are useful to them; but each knows naturally what is salutary and marvellously appropriates what suits its nature.
Source: Nine Homilies of Hexaemeron (New Advent)