I hate war, for it spoils conversation.

An educated mind is, as it were, composed of all the minds of preceding ages.

Leibniz never married; he had considered it at the age of fifty; but the person he had in mind asked for time to reflect. This gave Leibniz time to reflect, too, and so he never married.

I have lived one hundred years; and I die with the consolation of never having thrown the slightest ridicule upon the smallest virtue.

Women react differently: a French woman who sees herself betrayed by her husband will kill his mistress; an Italian will kill her husband; a Spaniard will kill both; and a German will kill herself.

The judgment may be compared to a clock or watch, where the most ordinary machine is sufficient to tell the hours; but the most elaborate alone can point out the minutes and seconds, and distinguish the smallest differences of time.

Nothing can be more destructive to ambition, and the passion for conquest, than the true system of astronomy. What a poor thing is even the whole globe in comparison of the infinite extent of nature!