I maintain that, if everyone knew what others said about him, there would not be four friends in the world; this is evident from the quarrels caused … - Blaise Pascal

I lay it down as a fact that if all men knew what others say of them, there would not be four friends in the world.

When I consider the brief span of my life absorbed into the eternity which precedes and will succeed it — memoria hospitis unius diei praetereuntis (remembrance of a guest who tarried but a day) — the small space I occupy and which I see swallowed up in the infinite immensity of spaces of which I know nothing and which know nothing of me, I take fright and am amazed to see myself here rather than there: there is no reason for me to be here rather than there, now rather than then. Who put me here? By whose command and act were this place and time allotted to me?

Can anything be stupider than that a man has the right to kill me because he lives on the other side of a river and his ruler has a quarrel with mine, though I have not quarrelled with him?

It is dangerous to explain too clearly to man how like he is to the animals without pointing out his greatness. It is also dangerous to make too much of his greatness without his vileness. It is still more dangerous to leave him in ignorance of both, but it is most valuable to represent both to him.
Man must not be allowed to believe that he is equal either to animals or to angels, nor to be unaware of either, but he must know both.