Is there anything so grave and serious as an ass?

Intelligence is required to be able to know that a man knows not.

I study myself more than any other subject. That is my metaphysics, that is my physics.

If ordinary people complain that I speak too much of myself, I complain that they do not even think of themselves.

While our pulse beats and we feel emotion, let us put off the business. Things will truly seem different to us when we have quieted and cooled down. It is passion that is in command at first, it is passion that speaks, it is not we ourselves.

It is a disaster that wisdom forbids you to be satisfied with yourself and always sends you away dissatisfied and fearful, whereas stubbornness and foolhardiness fill their hosts with joy and assurance.

Amongst all other vices there is none I hate more than cruelty, both by nature and judgment, as the extremest of all vices.