Elements of the philosophy of the human mind. By Dugald Stewart. Rev. and abridged, with critical and explanatory notes, for the use of colleges and schools. By Francis Bowen ...

132 ABSTRACTION.
general so much at a loss to convey their ideas as men of mechanical invention. This, I think, can only arise from their
being accustomed to direct their attention immediately to the
subjects of their consideration, without the use of signs. Philosophers who speculate on questions which require the employ.
ment of words as an instrument of thought, are seldom deficient
in a facility of expression.
Whether that particular species of mechanical contrivance
which has now been mentioned, and which consists merely in
employing a series of physical causes to accomplish an effect
which we cannot produce immediately, should or should not be
dignified with the name of reasoning, I shall not now inquire. It
is sufficient for my present purpose to remark, that it is essentially different from those intellectual processes to which the use
of signs is indispensably necessary. At the same time, I am
ready to acknowledge, that what I have now said, is not strictly
applicable to those more complicated mechanical inventions, in
which a variety of powers are made to conspire at once to produce a particular effect. Such contrivances, perhaps, may be
found to involve processes of the mind which cannot be carried
on without signs. But these questions will fall more properly
under our consideration when we enter on the subject of reasoning.
When words are necessary to thoughlt. - In general, it may be
remarked, that in so far as our thoughts relate merely to individual objects, or to individual events, which we have actually
(We need not question the good faith of the reporter of this anecdote.
The only doubt is, whether the animal had not previously, without his
knowledge, been taught how to use these expedients.)]
But admitting the facts to be accurately stated, they will still leave an
essential distinction between man and brutes; for in none of the contrivances here mentioned, is there any thing analogous to those intellectual
processes which lead the mind to general conclusions, and which (according to the foregoing doctrine) imply the use of general terms. Those
powers, therefore, which enable us to classify objects, and to employ signs
as an instrument of thought, are, as far as we can judge, peculiar to the human species.