prohairesis

In Aristotle, prohairesis names a deliberated choice — a preference reached by reasoning. Epictetus inherits the word and elevates it. For him, prohairesis is the centre of the self, the faculty by which we assent or refuse to impressions. It is also the one thing in his ontology that no one else can touch. The body, the reputation, the position — these can be seized. But the choice to grant or withhold assent is yours alone.

This is why Epictetus says, again and again, that the tyrant cannot harm you. He can chain you, exile you, kill you — but he cannot make you assent to the proposition that what he has done to you is evil. That is yours to give or withhold.

The common modern mistranslation is will in the volitional sense, as in "willpower." That misses it. Prohairesis is not the engine that drives action against resistance. It is the seat of consent — the place where you decide what counts as true, important, fearful, desirable. The whole Stoic project of prosochē (continuous attention) is the project of guarding this faculty from the impressions that would commandeer it.

When the passages call you free, this is what they mean. Not unconfined. Not autonomous in a political sense. Free in the sense that the one thing that matters about you cannot be coerced.