If pain is truly evil, it must harm either the body or the soul. But the body itself feels nothing — it's just matter. And the soul has the power to keep its peace and refuse to call pain evil. All our judgments and choices come from within. The sense that something is evil cannot reach us there unless we let it in through our own opinions.
If pain be an evil, either it is in regard of the body; (and that cannot be, because the body of itself is altogether insensible:) or in regard of the soul But it is in the power of the soul, to preserve her own peace and tranquillity, and not to suppose that pain is evil. For all judgment and deliberation; all prosecution, or aversation is from within, whither the sense of evil (except it be let in by opinion) cannot penetrate.