A quote
A certain person said to him (Epictetus): Frequently I desired to hear you and came to you, and you never gave me any answer; and now, if it is possible, I entreat you to say something to me. Do you think, said Epictetus, that as there is an art in anything else, so there is also an art in speaking, and that he who has the art, will speak skilfully, and he who has not, will speak unskilfully?
Epictetus·Discourses, "To or Against a Person Who Was One of Those Who Were Not Valued Esteemed by Him" (§1)·trans. Long