Stockdale on Stoicism 17

I think more needs to be said about good and evil. After all, the Stoic is indifferent to everything but good and evil. 

In Stoic thought, our good and our evil come from the same locus. "Vice and virtue reside in the will alone." "The essence of good and evil lies in an attitude of the will." 

Solzhenitsyn locates it in the heart, and Epictetus would buy that, or will, or moral purpose, or character, or soul, he's not a nitpicker about things like that. 

What he bears down on is that your good and your evil are the essence of you. You are moral purpose. You are rational will. You are not hair, you are not skin, you are moral purpose—get that beautiful, and you will be beautiful. 

—from James B. Stockdale, The Stoic Warrior's Triad