If we do not exert the right of eating our neighbor, it is because we have other means of making good cheer

No problem can withstand the assault of sustained thinking.

Let us confess it: evil strides the world.

Is there anyone so wise as to learn by the experience of others?

Descartes constructed as noble a road of science, from the point at which he found geometry to that to which he carried it, as Newton himself did after him. ... He carried this spirit of geometry and invention into optics, which under him became a completely new art.

Men must have somewhat altered the course of nature; for they were not born wolves, yet they have become wolves. God did not give them twenty-four-pounders or bayonets, yet they have made themselves bayonets and guns to destroy each other. In the same category I place not only bankruptcies, but the law which carries off the bankrupts’ effects, so as to defraud their creditors.

If there were no God, it would have been necessary to invent him.