Aristotle

=== Ethics ===
{{Main|Aristotelian ethics}}

Aristotle considered ethics to be a practical rather than theoretical study, i.e., one aimed at becoming good and doing good rather than knowing for its own sake. He wrote several treatises on ethics, most notably including the ''[[Nicomachean Ethics]]''.{{sfn| Kraut | 2001}}

Aristotle taught that virtue has to do with the proper function (''ergon'') of a thing. An eye is only a good eye in so much as it can see, because the proper function of an eye is sight. Aristotle reasoned that humans must have a function specific to humans, and that this function must be an activity of the ''[[De Anima|psuchē]]'' (''soul'') in accordance with reason (''[[logos]]''). Aristotle identified such an optimum activity (the virtuous mean, between the accompanying vices of excess or deficiency{{sfn|Humphreys|2009}}) of the soul as the aim of all human deliberate action, ''[[eudaimonia]]'', generally translated as "happiness" or sometimes "well-being". To have the potential of ever being happy in this way necessarily requires a good character (''ēthikē'' ''[[arete (moral virtue)|aretē]]''), often translated as moral or ethical virtue or excellence.{{sfn| Nicomachean Ethics | ps= &nbsp;Book I. See for example chapter 7.}}

Aristotle taught that to achieve a virtuous and potentially happy character requires a first stage of having the fortune to be habituated not deliberately, but by teachers, and experience, leading to a later stage in which one consciously chooses to do the best things. When the best people come to live life this way their practical wisdom (''[[phronesis]]'') and their intellect (''[[nous]]'') can develop with each other towards the highest possible human virtue, the wisdom of an accomplished theoretical or speculative thinker, or in other words, a philosopher.{{sfn| Nicomachean Ethics | p= Book VI}}