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 ...

ABSTRACTION. 125
IV. Inferences with respect to the use of language as an instrvment of thought, and the errors in reasoning to wzhich it occasionally gives rise. - In the-last section, I mentioned Dr. Campbell as an ingenious defender of the system of the Nominalists;
and I alluded to a particular application which he has made of
their doctrine. The reasonings which I had then in view, are
to be found in the seventh chapter of the second book of his
Philosophy of Rhetoric; in which chapter, he proposes to explain how it happens, " that nonsense so often escapes being detected, both by the writer and the reader." The title is somewhat ludicrous in a grave and philosophical work; but the disquisition to which it is prefixed contains many acute and proiound remarks on the nature and power of signs, both as a medium of communication, and as an instrument of thought.
Dr. Campbell's speculations with respect to language as an
instrument of thought, seem to have been suggested by the following passage in Mr. Hume's Treatise of Human Nature. " I
believe, every one who examines the situation of his mind in
reasoning will agree with me, that we do not annex distinct and
complete ideas to every term we make use of; and that in talking of government, church, negotiation, conquest, we seldom
spread out in our minds all the simple ideas of which these
complex ones are composed. It is,. however, observable, that
notwithstanding this imperfection, we may avoid talking nonsense on these subjects; and may perceive any repugnance
among the ideas, as well as if we had a full comprehension of
them. Thus if, instead of saying, that, in war, the weaker have
always recourse to negotiation, we should say, that they have
always recourse to conquest; the custom which we have acquired, of attributing certain relations to ideas, still follows the
words, and makes us immediately perceive the absurdity of that
proposition."
How we can use words with propriety, though without attaching any particular idea or signification to them. -In the remarks which Dr. Campbell has made on this passage, he has
endeavored to explain in what manner our habits of thinking
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