The self-indulgent man craves for all pleasant things... and is led by his appetite to choose these at the cost of everything else.
AristotleThe investigation of the truth is in one way hard, in another easy. An indication of this is found in the fact that no one is able to attain the truth adequately, while, on the other hand, no one fails entirely, but everyone says something true about the nature of all things, and while individually they contribute little or nothing to the truth, by the union of all a considerable amount is amassed.
AristotleSince the things we do determine the character of life, no blessed person can become unhappy. For he will never do those things which are hateful and petty.
AristotleThese two rational faculties may be designated the Scientific Faculty and the Calculative Faculty respectively; since calculation is the same as deliberation, and deliberation is never exercised about things that are invariable, so that the Calculative Faculty is a separate part of the rational half of the soul.
Aristotle