 For Plotinus, to say that something is “up to us” is to say that we have power or mastery over it. He contrasts this mastery with servitude or slavery. True power is the power to do what we wish, in order to gain what we desire. So Plotinus thinks that a person who acts under compulsion is not acting freely. He also agrees with Aristotle that a person who acts in ignorance of the particulars of his situation is not acting voluntarily: if I inadvertently poison my mother with cyanide-laced Tylenol, I am not doing what I wished to do, as I did not wish to poison my mother. But he disagrees with Aristotle, and agrees with Plato, in thinking that ignorance of the rightness or wrongness of what I propose to do excuses (Enn. VI.8[39].1). Plotinus believes that all desire is desire for the good (Enn. VI.8[39].7). If I poison my mother, I do so because I believe that doing so is good for me. But if I’m wrong about that, then when I kill her, I’m not really gaining what I desire, because I wanted to get what was good for me. (It’s for these sorts of reasons that Plato, in Gorgias 466c-468e, denies that a tyrant who is able to kill, torture, or imprison anybody as he sees fit has great power. Power enables a person to get what they desire, which is what is good for them, and the tyrant’s so-called “power” actually harms him.)