For the real difference between humans and other animals is that humans alone have perception of good and evil, just and unjust, etc. It is the sharing of a common view in these matters that makes a household and a state.
AristotleHe is his own best friend and takes delight in privacy whereas the man of no virtue or ability is his own worst enemy and is afraid of solitude.
AristotleWe must not listen to those who advise us 'being men to think human thoughts, and being mortal to think mortal thoughts' but must put on immortality as much as possible and strain every nerve to live according to that best part of us, which, being small in bulk, yet much more in its power and honour surpasses all else.
Aristotle