Letter 95 — On the Usefulness of Basic Principles (§39)

“Suppose that a man is acting as he should; he cannot keep it up continuously or consistently, since he will not know the reason for so acting. Some of his conduct will result rightly because of luck or practice; but there will be in his hand no rule by which he may regulate his acts, and which he may trust to tell him whether that which he has done is right. One who is good through mere chance will not give promise of retaining such a character for ever.”