Solum sapientem esse liberum, et omnem stultum servum.Hint # 1: It's Paradox # V
Only the wise man is free, and every foolish man is a slave.
Courtesy of translator Giles Laurén, author of The Stoic's Bible.
Hint # 2: Here's a picture of the author:
Hint # 3: He's a Republican era Roman.