Augustine of Hippo

(in Joh. tr. 1. c. 18) Life of itself gives illumination to men, but to cattle not: for they have not rational souls, by which to discern wisdom: whereas man, being made in the image of God, has a rational soul, by which he can discern wisdom. Hence that life, by which all things are made, is light, not however of all animals whatsoever, but of men.