All men, or most men, wish what is noble but choose what is profitable; and while it is noble to render a service not with an eye to receiving one in return, it is profitable to receive one. One ought therefore, if one can, to return the equivalent of services received, and to do so willingly; for one ought not to make a man one's friend if one is unwilling to return his favors.
AristotleIt is not easy for a person to do any great harm when his tenure of office is short, whereas long possession begets tyranny.
AristotleThe happy life is regarded as a life in conformity with virtue. It is a life which involves effort and is not spent in amusement.
AristotleThe structural unity of the parts is such that, if any one of them is displaced or removed, the whole will be disjointed and disยญturbed. For a thing whose presence or absence makes no visible difference is not an organic part of the whole.
Aristotle