My intention then in displaying so carefully the arguments of that
fantastic sect, is only to make the reader sensible of the truth of my
hypothesis, that all our reasonings concerning causes and effects are
derived from nothing but custom; and that belief is more properly an act
of the sensitive, than of the cogitative part of our natures. I
have here proved, that the very same principles, which make us form
a decision upon any subject, and correct that decision by the
consideration of our genius and capacity, and of the situation of our
mind, when we examined that subject; I say, I have proved, that these
same principles, when carryed farther, and applied to every new reflex
judgment, must, by continually diminishing the original evidence, at
last reduce it to nothing, and utterly subvert all belief and opinion.
If belief, therefore, were a simple act of the thought, without any
peculiar manner of conception, or the addition of a force and vivacity,
it must infallibly destroy itself, and in every case terminate in a
total suspense of judgment. But as experience will sufficiently convince
any one, who thinks it worth while to try, that though he can find no
error in the foregoing arguments, yet he still continues to believe, and
think, and reason as usual, he may safely conclude, that his reasoning
and belief is some sensation or peculiar manner of conception, which it
is impossible for mere ideas and reflections to destroy.
But here, perhaps, it may be demanded, how it happens, even upon my
hypothesis, that these arguments above-explained produce not a total
suspense of judgment, and after what manner the mind ever retains a
degree of assurance in any subject? For as these new probabilities,
which by their repetition perpetually diminish the original evidence,
are founded on the very same principles, whether of thought or
sensation, as the primary judgment, it may seem unavoidable, that in
either case they must equally subvert it, and by the opposition,
either of contrary thoughts or sensations, reduce the mind to a total
uncertainty. I suppose, there is some question proposed to me, and
that after revolving over the impressions of my memory and senses,
and carrying my thoughts from them to such objects, as are commonly
conjoined with them, I feel a stronger and more forcible conception on
the one side, than on the other. This strong conception forms my first
decision. I suppose, that afterwards I examine my judgment itself,
and observing from experience, that it is sometimes just and sometimes
erroneous, I consider it as regulated by contrary principles or causes,
of which some lead to truth, and some to error; and in ballancing these
contrary causes, I diminish by a new probability the assurance of my
first decision. This new probability is liable to the same diminution as
the foregoing, and so on, IN INFINITUM. It is therefore demanded, how
it happens, that even after all we retain a degree of belief, which is