The safest way for a state is to lay down the rule that religion is comprised solely in the exercise of charity and justice, and that the rights of rulers in sacred, no less than in secular matters, should merely have to do with actions, but that every man should think what he likes and say what he thinks.

So long as a man imagines that he cannot do this or that, so long as he is determined not to do it; and consequently so long as it is impossible to him that he should do it.

Things which are accidentally the causes either of hope or fear are called good or evil omens.

Everything great is just as difficult to realize as it is rare to find.

He alone is free who lives with free consent under the entire guidance of reason.

In the mind there is no absolute or free will.

I make this chief distinction between religion and superstition, that the latter is founded on ignorance, the former on knowledge.