All that belongs to human understanding, in this deep ignorance and obscurity, is to be sceptical, or at least cautious, and not to admit of any hypothesis whatever, much less of any which is supported by no appearance of probability.

We learn the influence of our will from experience alone. And experience only teaches us, how one event constantly follows another; without instructing us in the secret connexion, which binds them together, and renders them inseparable.

I never asserted such an absurd thing as that things arise without a cause.

The imagination of man is naturally sublime, delighted with whatever is remote and extraordinary, and running, without control, into the most distant parts of space and time in order to avoid the objects, which custom has rendered too familiar to it.

... superstitions, which, being unable to defend themselves on fair ground, raise these intangling brambles to cover and protect their weakness. Chased from the open country, these robbers fly into the forest, and lie in wait to break in upon every unguarded avenue of the mind, and overwhelm it with religious fears and prejudices. ... The idea of God, as meaning an infinitely intelligent, wise and good Being, arises from reflecting on the operations of our own mind, and augmenting, without limit, those qualities of goodness and wisdom.

The bigotry of theologians is a malady which seems almost incurable.

When I shall be dead, the principles of which I am composed will still perform their part in the universe, and will be equally useful in the grand fabric, as when they composed this individual creature. The difference to the whole will be no greater betwixt my being in a chamber and in the open air. The one change is of more importance to me than the other; but not more so to the universe.