Letters 47.19

So I hold that you are entirely right in not wishing to be feared by your slaves, and in lashing them merely with the tongue; only dumb animals need the thong.

That which annoys us does not necessarily injure us; but we are driven into wild rage by our luxurious lives, so that whatever does not answer our whims arouses our anger.

Seneca, Letters to Lucilius 47.19, translated by Richard Mott Gummere