this
inconsistency, and followed out the general theorem
respecting the logical value of the syllogism to its
legitimate corollary, have been led to impute
uselessness and frivolity to the syllogistic theory
itself, on the ground of the _petitio principii_ which
they allege to be inherent in every syllogism. As I
believe both these opinions to be fundamentally
erroneous, I must request the attention of the reader to
certain considerations, without which any just
appreciation of the true character of the syllogism, and
the functions it performs in philosophy, appears to me
impossible; but which seem to me to have been overlooked
or insufficiently adverted to, both by the defenders of
the syllogistic theory, and by its assailants.

"It must be granted, that in every syllogism, considered
as an argument to prove the conclusion, there is a
_petitio principii_. When we say--

'All men are mortal.
Socrates is a man;
THEREFORE
Socrates is mortal'--

it is unanswerably urged by the adversaries of the
syllogistic theory, that the proposition, Socrates is
mortal, is presupposed in the more general assumption,
All men are mortal; that we cannot be assured of the
mortality of all men, unless we were previously certain
of the mortality of every individual man; that if it be
still doubtful whether Socrates, or any other individual
you choose to name, be mortal or not, the same degree of
uncertainty must hang over the assertion, All men are
mortal; that the general principle, instead of being
given as evidence of the particular case, cannot itself
be taken for true without exception, until every shadow
of doubt which could affect any case comprised with it,
is dispelled by evidence _aliunde_, and then what
remains for the syllogism to prove? that, in short, no
reasoning from generals to particulars can, as such,
prove any thing; since from a general principle you
cannot infer any particulars, but those which the
principle itself assumes as foreknown.

"This doctrine is irrefragable; and if logicians, though
unable to dispute it, have usually exhibited a strong
disposition to explain it away, this was not because
they could discover any flaw in the argument itself, but
because the contrary opinion seemed to rest upon
argu