WILL you say that there is nothing independent which is in your own power alone, and unalienable? See, then, if you have anything of this sort. — "I do not know." But, consider it thus: Can anyone make you assent to a falsehood? — "No one." In the topic of assent, then, you are unrestrained and unhindered. — "Agreed." Well, and can anyone compel you to exert your pursuits towards what you do not like ? — "He can. For when he threatens me with death, or fetters, he compels me to exert them." If, then, you were to despise dying, or being fettered, would you any longer regard him? — "No." Is despising death, then, an action in our power, or is it not? — "It is." Is it, therefore, in your power also to exert your pursuits towards anything, or is it not? — "Agreed that it is. But in whose power is my avoiding anything?" This too, is in your own. — "What then, if, when I am exerting myself to walk, anyone should restrain me?" What part of you can he restrain? Can he restrain your assent? — "No, but my body." Ay, as he may a stone. — "Be it so. But still I walk no more." And who told you that walking was an action of your own that cannot be restrained? For I only said that your exerting yourself towards it could not be restrained.
EPICTETUS. DISCOURSES. Book iv. §1, ¶11.