A System of Logic: Ratiocinative and Inductive, 7th Edition, Vol. I — John Stuart Mill — John Shaqi
A System of Logic: Ratiocinative and Inductive, 7th Edition, Vol. I
John Stuart Mill · en
After the explanations so fully entered into on the subject of
propositions, much further discussion cannot be necessary to make the
radical error of this view of ratiocination apparent. If the word man
connoted mortality; if the meaning of "mortal" were involved in the
meaning of "man;" we might, undoubtedly, evolve the conclusion from the
minor alone, because the minor would have already asserted it. But if,
as is in fact the case, the word man does not connote mortality, how
does it appear that in the mind of every person who admits Socrates to
be a man, the idea of man must include the idea of mortality? Dr. Brown
could not help seeing this difficulty, and in order to avoid it, was
led, contrary to his intention, to re-establish, under another name,
that step in the argument which corresponds to the major, by affirming
the necessity of _previously perceiving_ the relation between the idea
of man and the idea of mortal. If the reasoner has not previously
perceived this relation, he will not, says Dr. Brown, infer because
Socrates is a man, that Socrates is mortal. But even this admission,
though amounting to a surrender of the doctrine that an argument
consists of the minor and the conclusion alone, will not save the
remainder of Dr. Brown's theory. The failure of assent to the argument
does not take place merely because the reasoner, for want of due
analysis, does not perceive that his idea of man includes the idea of
mortality; it takes place, much more commonly, because in his mind that
relation between the two ideas has never existed. And in truth it never
does exist, except as the result of experience. Consenting, for the sake
of the argument, to discuss the question on a supposition of which we
have recognised the radical incorrectness, namely, that the meaning of a
proposition relates to the ideas of the things spoken of, and not to
the things themselves; I must yet observe, that the idea of man, as an
universal idea, the common property of all rational creatures, cannot
involve anything but what is strictly implied in the name. If any one
includes in his own private idea of man, as no doubt is always the case,
some other attributes, such for instance as mortality, he does so only
as the consequence of experience, after having satisfied himself that
all men possess that attribute: so that whatever the idea contains, in
any person's mind, beyond what is included in the conventional
signification of the word, has been added to it as the result of assent
to a proposition; while Dr. Brown's theory requires us to suppose, on
the contrary, that assent to the proposition is produced by evolving,
through an analytic process, this very element out of the idea. This
theory, therefore, may be considered as sufficiently refuted; and the
minor premise must be regarded as totally insufficient to prove the
conclusion, except with the assistance of the major, or of that which
the major represents, namely, the various singular propositions