As soon as an opinion becomes common it is sufficient reason for men to abandon it and to uphold the opposite opinion until that in its turn grows old, and they require to distinguish themselves by other things. Thus if they attain their goal in some art or science, we must expect them soon to cast it aside to acquire some fresh fame, and this is partly the reason why the most splendid ages degenerate so quickly, and, scarcely emerged from barbarism, plunge into it again.

Our errors and our controversies, in the sphere of morality, arise sometimes from looking on men as though they could be altogether bad, or altogether good.

The counsels of old age give light without heat, like the sun in winter.

Clearness marks the sincerity of philosophers.

The fool is like those people who think themselves rich with little.

We are so presumptuous that we think we can separate our personal interest from that of humanity, and slander mankind without compromising ourselves.

Persevere in the fight, struggle on, do not let go, think magnanimously of man and life, for man is good and life is affluent and fruitful.