[50] and this is the meaning of the oracle recorded in Deuteronomy, "Behold, I have put before thy face life and death; good and evil. Do thou choose life." [23] Therefore he teaches us by this sentence both that men have a knowledge of good and of the contrary, evil, and that it is their duty to choose the better in preference to the worse, preserving reason within themselves as an incorruptible judge, to be guided by the arguments which sound sense suggests, and to reject those which are brought forward by the contrary power.