evident," as Philo calls it, Hume spends the greatest care in
showing that it is nothing but the product of custom, or experience.

And the doubt thus forced upon one, whether Philo ought to be taken as
even, so far, Hume's mouth-piece, is increased when we reflect that we
are dealing with an acute reasoner; and that there is no difficulty in
drawing the deduction from Hume's own definition of a cause, that the
very phrase, a "first cause," involves a contradiction in terms. He lays
down that,--

"'Tis an established axiom both in natural and moral philosophy,
that an object, which exists for any time in its full perfection
without producing another, is not its sole cause; but is assisted
by some other principle which pushes it from its state of
inactivity, and makes it exert that energy, of which it was
secretly possessed."--(I. p. 106.)

Now the "first cause" is assumed to have existed from all eternity, up
to the moment at which the universe came into existence. Hence it cannot
be the sole cause of the universe; in fact, it was no cause at all until
it was "assisted by some other principle"; consequently the so-called
"first cause," so far as it produces the universe, is in reality an
effect of that other principle. Moreover, though, in the person of
Philo, Hume assumes the axiom "that whatever begins to exist must have a
cause," which he denies in the _Treatise_, he must have seen, for a
child may see, that the assumption is of no real service.

Suppose Y to be the imagined first cause and Z to be its effect. Let the
letters of the alphabet, _a_, _b_, _c_, _d_, _e_, _f_, _g_, in their
order, represent successive moments of time, and let _g_ represent the
particular moment at which the effect Z makes its appearance. It follows
that the cause Y could not have existed "in its full perfection" during
the time _a_--_e_, for if it had, then the effect Z would have come into
existence during that time, which, by the hypothesis, it did not do. The
cause Y, therefore, must have come into existence at _f_, and if
"everything that comes into existence has a cause," Y must have had a
cause X operating at _e_; X, a cause W operating at _d_; and, so on, _ad
infinitum_.[31]

If the only demonstrative argument for the existence of a Deity, which
Hume advances, thus, literally, "goes to water" in the solvent of his
philosophy, the reasoning from the evidence of design does not fare much
better. If