A quote
The carpenter does not need to inquire about his art in the light of its origin or of its function, any more than a pantomime need inquire about the art of dancing; if these arts understand themselves, nothing is lacking, for they do not refer to life as a whole. But virtue means the knowledge of other things besides herself: if we would learn virtue we must learn all about virtue.
Seneca·Letter 95 — On the Usefulness of Basic Principles (§56)·trans. Gummere