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 ...

118 ABSTRACTION.
same, as to authorize us to lay down as a principle, that, with,
out the use of signs, all our thoughts must have related to individuals. When we reason, therefore, concerning classes or genera, the objects of our attention are merely signs; or if, in any
instance, the generic word should recall some individual, this
circumstance is to be regarded only as the consequence of an
accidental association, which has rather a tendency to disturb,
than to assist us in our reasoning.
Whether it might not have been possible for the Deity to
have so formed us, that we might have been capable of reasoning concerning classes of objects, without the use of signs, I
shall not take upon me to determine. But this we may ventureto affirm with confidence, that man is not such a being. And,
indeed, even if he were, it would not therefore necessarily follow, that there exists any thing in a genus, distinct from the
individuals of which it is composed; for we know that the
power which we have of thinking of particular objects without
the medium of signs, does not in the least depend on their ex
istence or non-existence at the moment we think of them.
It would be vain, however, for us, in inquiries of this nature,
to indulge ourselves in speculating about possibilities. It is of
more consequence to remark the advantages which we derive
from our actual constitution, and which, in the present instance,
appear to me to be important and admirable; inasmuch as it
fits mankind for an easy interchange of their intellectual acquisitions, by imposing on them the necessity of employing, in their
solitary speculations, the same instrument of thought, which
forms the established medium of their communications with each
other.*
[See note to page 77.
It must be admitted, that, in other passages of his philosophical writings, Stewart does not seem to be always mindful of tile doctrine which he
has here labored to establish. Take the following, for instance, from "Note
Q" to the First Part of his Dissertation on the Progress of Metaphysical
Philosophy. In answer to a remark by Bonnet, that privation of one of the
senses entails a loss of all the ideas usually obtained through that sense, he
says, " The question is not about our ideas of the material world, but about