n afterwards to doubt or to disbelieve;
and the prevalence of many false beliefs, sincerely cherished and
zealously maintained, raises the question, how we may best discriminate
between truth and error? Hence the various theories of Certitude, and
hence also the antagonist theories of Skepticism.

The theories of Certitude may be reduced to _three_ classes. The _first_
places the ground of Certitude in _Reason_; the _second_ in _Authority_;
the _third_, in _Evidence_, including under that term both the external
manifestations of truth, and the internal principles or laws of thought
by which we are determined in forming our judgments in regard to them.
Each of these theories, however, has appeared in various phases in the
history of philosophical speculation. The Individual Reason of
Martineau, the Generic Reason of Lamennais, the Impersonal Reason of
Cousin, the Authority of the Race, and the Infallibility of the Church,
are specimens of these varieties.

The theory which places the principle of Certitude in REASON has assumed
at least two distinct shapes. In the one it discards all authority
except that of private judgment or individual reason; in the other it
appeals to a higher reason, which is said to be impersonal and
infallible, and which is supposed to regulate and determine the
convictions of the human mind. In the former shape, it appears in the
speculations of Martineau; in the latter, it is advocated by Cousin; and
in one or other of these shapes it constitutes the ground-principle of
RATIONALISM. The theory, again, which places the principle of Certitude
in AUTHORITY has also assumed two distinct shapes. In the one it speaks
of a universal consent or Generic Reason, the reason not of the
individual but of the race to which he belongs, and exhibits a singular
combination of the Philosophy of Common Sense as taught by Dr. Reid and
the Scottish School, with the principle of Authoritative Tradition as
taught in the Popish Church; in the other, it refers more specifically,
not to the infallibility of the race at large, but to the infallibility
of a select body, regularly organized and invested with peculiar powers,
into whose hands has been committed the sacred deposit and the sole
guardianship of truth, whether in matters of philosophy or faith. In
both forms it is presented in the writings of M. Gerbet and M.
Lamennais, and in both it is necessary for the full maintenance of the
Popish system of doctrine. The