All of us, he used to say, are so fashioned by nature that we can live our lives free from error and nobly; not that one can and another cannot, but all. The clearest evidence of this is the fact that lawgivers lay down for all alike what may be done and forbid what may not be done, exempting from punishment no one who disobeys or does wrong, not the young nor the old, not the strong nor the weak, not anyone whomsoever. And yet if the whole notion of virtue were something that came to us from without, and we share no part of it by birth, just as in activities pertaining to the other arts no one who has not learned the art is expected to be free from error, so in like manner in things pertaining to the conduct of life it would not be reasonable to expect anyone to be free from error who had not learned virtue, seeing that virtue is the only thing that saves us from error in daily living. Now in the care of the sick we demand no one but the physician to be free from error, and in handling the lyre no one but the musician, and in managing the helm no one but the pilot, but in the conduct of life it is no longer only the philosopher whom we expect to be free from error, though he alone would seem to be the only one concerned with the study of virtue, but all men alike, including those who have never given any attention to virtue. Clearly, then, there is no explanation for this other than that the human being is born with an inclination toward virtue. And this indeed is strong evidence of the presence of goodness in our nature, that all speak of themselves as having virtue and being good. For take the common man; when asked whether he is stupid or intelligent, not one will confess to being stupid; or again, when asked whether he is just or unjust, not one will say that he is unjust. In the same way, if one asks him whether he is temperate or intemperate, he replies at once that he is temperate; and finally, if one asks whether he is good or bad, he would say that he is good, even though he can name no teacher of virtue or mention any study or practice of virtue he has ever made. Of what, then, is this evidence if not of the existence of an innate inclination of the human soul toward goodness and nobleness, and of the presence of the seeds of virtue in each one of us? Moreover, because it is entirely to our advantage to be good, some of us deceive ourselves into thinking that we are really good, while others of us are ashamed to admit that we are not. Why then pray, when one who has not learned letters or music or gymnastics never claims to have knowledge of these arts nor makes any pretense of knowing them, and is quite unable even to name a teacher to whom he went, why, I say, does everyone profess that he has virtue? It is because none of those other skills is natural to man, and no human being is born with a natural facility for them, whereas an inclination toward virtue is inborn in each one of us.
Musonius Rufus, Discourses