Whatever we conceive as existent, we can also conceive as non-existent.

There is no being, therefore, whose non-existence implies a contradiction.

Consequently there is no being, whose existence is demonstrable.

I propose this argument as entirely decisive, and am willing to rest the whole controversy upon it.
It is pretended that the Deity is a necessarily existent being; and this necessity of his existence is attempted to be explained by asserting, that if we knew his whole essence or nature, we should perceive it to be as impossible for him not to exist, as for twice two not to be four.

But it is evident that this can never happen, while our faculties remain the same as at present.