Aristotle, Nicomachean Ethics
H. Rackham, Ed.

and might have known without difficulty; [9] and so in other cases where ignorance is held to be due to negligence, on the ground that the offender need not have been ignorant, as he could have taken the trouble to ascertain the facts. [10]

It may be objected that perhaps he is not the sort of man to take the trouble. Well, but men are themselves responsible for having become careless through living carelessly, as they are for being unjust or profligate if they do wrong or pass their time in drinking and dissipation. They acquire a particular quality by constantly acting in a particular way. [11] This is shown by the way in which men train themselves for some contest or pursuit: they practice continually. [12] Therefore only an utterly senseless person can fail to know that our characters are the result of our conduct;¹ but if a man knowingly acts in a way that will result in his becoming unjust, he must be said to be voluntarily unjust. [13]

Again, though it is unreasonable to say that a man who acts unjustly or dissolutely does not wish to be unjust or dissolute, [14] nevertheless this by no means implies that he can stop being unjust and become just merely by wishing to do so; any more than a sick man can get well by wishing, although it may be the case that his illness is voluntary, in the sense of being due to intemperate living and neglect of the doctors' advice. At the outset then, it is true, he might have avoided the illness, but once he has let himself go he can do so no longer. When you have thrown a stone, you cannot afterwards bring it back again, but nevertheless you are responsible for having taken up the stone and flung it, for the origin of the act was within you. Similarly the unjust