The most dangerous madmen are those created by religion, and people whose aim is to disrupt society always know how to make good use of them on occasion.

There is not a Musselman alive who would not imagine that he was performing an action pleasing to God and his Holy Prophet by exterminating every Christian on earth, while the Christians are scarcely more tolerant on their side.

When we know to read our own hearts, we acquire wisdom of the heartsof others.

You live as if you were destined to live forever, no thought of your frailty ever enters your head, of how much time has already gone by you take no heed. You squander time as if you drew from a full and abundant supply, so all the while that day which you bestow on some person or thing is perhaps your last. You have all the fears of mortals and all the desires of immortals… What foolish forgetfulness of mortality to defer wise resolutions to the fiftieth or sixtieth year, and to intend to begin life at a point to which few have attained.

In order to get as much fame as one's father one has to much more able than he.

A thing is not proved just because no one has ever questioned it. What has never been gone into impartially has never been properly gone into. Hence scepticism is the first step toward truth. It must be applied generally, because it is the touchstone.

Integrity is the evidence of all civil virtues.