Stoic Psychology 101

Impressions, Assent, and Impulses

This is one of the most famous and important passages in all extant Stoic literature:

So make a practice at once of saying to every strong impression: ‘An impression is all you are, not the source of the impression.’ Then test and assess it with your criteria, but one primarily: ask, ‘Is this something that is, or is not, in my control?’ (Epictetus, Enchiridion 1.5)

If we understand this then we are already a long way toward understanding Stoic philosophy as a whole. And if we practice it regularly, we put ourselves on the path to ataraxia, a state of serenity that comes with always acting properly in the world.

So what on earth is Epictetus talking about? What is an “impression,” and how do we talk to it? To grasp this concept we need first to engage in a bit of Stoic Psychology 101. We are about to encounter some unfamiliar concepts and Greek words. But I guarantee you, the payoff is huge, so bear with me.

To begin with, let’s talk about emotions, or what the Stoics called “passions.” The classic book on this is Margaret Graver’s Stoicism and Emotion, about which…