Note: this is the ninth part of a weekly series, in which I translate and discuss the Enchiridion (Handbook) of Epictetus. New posts will be released every monday morning (GMT).

We have learned that we are not disturbed by things, but merely by our opinions of them. In the ninth paragraph of the Enchiridion, Epictetus elaborates on this. He states that physical discomforts cannot hurt us, unless we choose to let them hurt us:

Disease is an impediment to the body, but not to the power of choice, unless it chooses so itself. Lameness is an impediment to the leg, but not to the power of choice. And say this to everything that happens to you: for you will find that anything is an impediment to something else, but not to you.

Essentially, Epictetus argues that external disturbances can’t reach us if we deny them access. Disease, pain and afflictions can be kept out, if we choose so. They are like a foreign army standing outside the city walls. The only way to let them in, is by opening the gates. But if we choose to close the gates, they cannot enter.

Yet you may ask: is it not a hindrance that my body is hurt by disease? Or that my leg is suffering lameness? While asking this, remember that our body is not ours: we don’t control it. Our shape is not our identity. It is not physical comfort that we are after, but mental tranquility.

And it is our own power of choice that governs this tranquility. The entire paragraph can be summarized in one concept, that a central concept to stoicism in general and to Epictetus specifically. This is ‘prohairesis’ (προαίρεσις), which I have translated here as ‘power of choice’. It is the human capacity to deal with appearances or impressions (phantasiai; φαντασίαι). It is, indeed, our capability to give or withold assent to external circumstances. We can either let the army march in the city, or stop it at the gates. We can let disease and pain ravage and destroy our inner peace, or we can choose to keep it out.