Book 2
2
Now the voluntary seems to be the opposite of the involuntary; and acting with knowledge of either the person acted on or the instrument or the result (for sometimes the agent knows that it is his father but does not intend to kill him but to save him—as the PeliadsThe daughters of Pelias, King of Iolchus, cut him up and boiled him, having been told by Medea (who wanted Jason to leave his throne) that this would restore his youth. did—or knows that what he is offering is a drink but offers it as a love-charm or wine, when really it is hemlock) seems to be the opposite of acting without knowing the person acted on, the instrument and the nature of the act, through ignorance and not by accident. But to act through ignorance of the act, the means and the person acted on is involuntary action.
3
Therefore the opposite is voluntary. It follows then that all the things that a man does not in ignorance, and through his own agency, when it is in his power not to do them, are voluntary acts, and it is in this that the voluntary consists; and all the things that he does in ignorance, and through being in ignorance, he does involuntarily.
