pplication of the Scottish doctrine of Common Sense, such as may be
highly serviceable to the Church of Rome. Protestant writers, indeed,
have sometimes appealed to _common consent_ as a collateral proof,
auxiliary to that which is more direct and conclusive; but they have
done so merely because they regarded it as a _part of the evidence_,
well fitted to prove what Dr. Cudworth calls "the naturality of the idea
of God," and not because they confounded it with the _faculty_ by which
alone that evidence can be discerned and appreciated. They never
regarded it as the sole ground of certainty either in matters of
Philosophy or Faith. Nor can it be so considered by any thoughtful mind.
For how can I be more assured of an _impersonal reason_ than of my own?
How can I be more certain of the existence and the traditions of other
men, than of the facts of my own consciousness, and the spontaneous
convictions of my own understanding? or how can I be assured that, in
passing from the impersonal reason to the individual mind, from the
generic reason to the personal, the truth may not contract some taint of
weakness or impurity from the vessel in which it is ultimately
contained,--from the finite faculties by which alone it is apprehended
and believed?

The fact is that any attempt to prove the truth of our faculties must
necessarily fail. Did we set ourselves to the task of proving by
argument or by authority that we are not wrong in believing in our own
existence or that of an external world, or did we attempt to establish
the trustworthiness of our faculties by resolving it into the veracity
of God, our effort must needs be as abortive as it is superfluous, since
it involves the necessity not only of proving the fact, but of _proving
the proof itself_, and that, too, by the aid of the very faculties whose
trustworthiness is in question! There are certain ultimate facts beyond
which it is impossible to push our speculative inquiries; certain first
or fundamental principles of Reason, which are in themselves
indemonstrable, but which constitute the ground or condition of all
demonstration; certain intuitive perceptions, which are widely different
from rational deductions, but which determine and govern every process
of reasoning and every form of belief. To deny the _certainty_ of our
intuitive perceptions, merely because we cannot prove by argument the
truth of our mental faculties, would virtually amount to a rejection of
all ev