Chapter 34.—It is One Thing to
Know the Laws of Inference, Another to Know the Truth of
Opinions.
52. Therefore it is one thing to
know the laws of inference, and another to know the truth of
opinions. In the former case we learn what is consequent, what is
inconsequent, and what is incompatible. An example of a
consequent is, “If he is an orator, he is a man;” of an
inconsequent, “If he is a man, he is an orator;” of an
incompatible, “If he is a man, he is a quadruped.” In these
instances we judge of the connection. In regard to the truth of
opinions, however, we must consider propositions as they stand by
themselves, and not in their connection with one another; but when
propositions that we are not sure about are joined by a valid
inference to propositions that are true and certain, they
themselves, too, necessarily become certain. Now some, when they
have ascertained the validity of the inference, plume themselves as
if this involved also the truth of the propositions. Many, again,
who hold the true opinions have an unfounded contempt for
themselves, because they are ignorant of the laws of inference;
whereas the man who knows that there is a resurrection of the dead
is assuredly better than the man who only knows that it follows
that if there is no resurrection of the dead, then is Christ not
risen.