If... the ability to tell right from wrong should turn out to have anything to do with the ability to think, then we must be able to "demand" its exercise from every sane person, no matter how erudite or ignorant, intelligent or stupid, he may happen to be. Kant—in this respect almost alone among the philosophers—was much bothered by the common opinion that philosophy is only for the few, precisely because of its moral implications.

p. 13. - The Life of the Mind (1971/1978)