BOOK I PART III
ideas, and from the discovery of such relations
as are unalterable, so long as the ideas continue
the same. These relations areresemblance, pro-
portions in quantity and number, degrees or any
quality, and contrarietyi; none of which are im-
plyed in this proposition, Whatever has a be-
ginning has also a cause of existence. That
proposition therefore is not intuitively certain.
At least any one, who would assert it to be intu-
itively certain, must deny these to be the only
infallible relations, and must find some other
relation of that kind to be implyed in it; which
it will then be time enough to examine.
But here is an argument, which proves at
once, that the foregoing proposition is neither
intuitively nor demonstrably certain. We can
never demonstrate the necessity of a cause to
every new existence, or new modification of ex-