to make use of those observations, I have already made, that the idea of
production is the same with that of causation, and that no existence
certainly and demonstratively implies a power in any other object; or
were it proper to anticipate what I shall have occasion to remark
afterwards concerning the idea we form of power and efficacy. But as such
a method of proceeding may seem either to weaken my system, by resting
one part of it on another, or to breed a confusion in my reasoning, I
shall endeavour to maintain my present assertion without any such
assistance.

It shall therefore be allowed for a moment, that the production of one
object by another in any one instance implies a power; and that this
power is connected with its effect. But it having been already proved,
that the power lies not in the sensible qualities of the cause; and there
being nothing but the sensible qualities present to us; I ask, why in
other instances you presume that the same power still exists, merely upon
the appearance of these qualities? Your appeal to past experience decides
nothing in the present case; and at the utmost can only prove, that that
very object, which produced any other, was at that very instant endowed
with such a power; but can never prove, that the same power must continue
in the same object or collection of sensible qualities; much less, that a
like power is always conjoined with like sensible qualities. should it be
said, that we have experience, that the same power continues united with
the same object, and that like objects are endowed with like powers, I
would renew my question, why from this experience we form any conclusion
beyond those past instances, of which we have had experience. If you
answer this question in, the same manner as the preceding, your answer
gives still occasion to a new question of the same kind, even in
infinitum; which clearly proves, that the foregoing reasoning had no just
foundation.