What is the highest of all goods achievable by action? ...both the general run of man and people of superior refinement say that it is happiness ...but with regard to what happiness is they differ.
It is just that we should be grateful, not only to those with whose views we may agree, but also to those who have expressed more superficial views; for these also contributed something, by developing before us the powers of thought.
Virtue also depends on ourselves. And so also does vice. For where we are free to act we are also free to refrain from acting, and where we are able to say No we are also able to say Yes; if therefore we are responsible for doing a thing when to do it right, we are also responsible for not doing it when not to do it is wrong, and if we are responsible for rightly not doing a thing, we are also responsible for wrongly doing it.
Nature, as we say, does nothing without some purpose; and for thepurpose of making mana political animal she has endowed him alone among the animals with the power of reasoned speech.