EPICTETUS. DISCOURSES. Book ii. §9. ¶2.
ALL are preserved and improved by operations correspondent to their several faculties; as a carpenter, by building; a grammarian, by grammar; but if he accustom himself to write ungrammatically, his art will necessarily be spoiled and destroyed. Thus modest actions preserve the modest man, and immodest ones destroy him; faithful actions, the faithful man, and the contrary destroy him. On the other hand, contrary actions heighten contrary characters. Thus impudence, an impudent one; knavery, a knavish one; slander, a slanderous one; anger, an angry one; and inequitable dealings, a covetous one.