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introductive argument. I furthermore show that they
invariably leave the doors open, theoretically and
practically, a bad reasoning. In fact, there are no rules at all,
for the most part, which follow as necessary corollaries from these
theories. From the ordinary theories of hypothesis, on
the other hand, rules do flow; buth they are particularly
pestiferous rules, much worse than none at all; and
these unfortunately have bocome, through judge's
changes is juries and otherwise, widely current away
people who ever opened a book of logic.

Having this examined the general docturne of the
validity of reasonings, I next consider the trutch of
propositions not based on reasonings, such as axions,
facts of perception, moral judgements, and the like.

As a supplement to Critical Logic, I add a
chapter upon fallacies, the ordinary ones, some
mathematical fallacies, fallacies of introduction and