The principal axiom in their theory was: Everything can be proved, and everything can be disproved; and in the process, one must profit as much from the folly of others, and from his own superiority, as he can.

I am, therefore there is a God.

Judaism boasts of no exclusive revelation of eternal truths that are indispensable to salvation, of no revealed religion in the sense in which that term is usually understood.

Reader! To whatever visible church, synagogue, or mosque you may belong! See if you do not find more true religion among the host of the excommunicated than among the far greater host who excommunicated them.

My religion recognizes no obligation to resolve doubt other than through rational means; and it commands no mere faith in eternal truths

We consider the beauty of nature and art with pleasure and satisfaction, without the slightest movement of desire. Instead, it appears to be a particular mark of beauty that it is considered with tranquil satisfaction; that it pleases if we also do not possess it and we are still far removed from demanding to possess it

I fear that, in the end, the famous debate among materialists, idealists, and dualists amounts to a merely verbal dispute that is more a matter for the linguist than for the speculative philosopher