— 423 —
      §9. Nor have the Modern Philosophers, who have endeavoured
to throw off the Jargon of the Schools, and speak intelligibly, much
better succeeded in defining simple Ideas, whether by explaining
their Causes, or any otherwise. The Atomists, who define Motion to
be a passage from one place to another, What do they more than put one
synonymous Word for another? For what is Passage other than
Motion? And if they were asked what Passage was, How would
they better define it than by Motion? For is it not at least as proper
and significant, to say, Passage is a Motion from one place to another, as to
say, Motion is a passage, etc. This is to translate, and not to define,
when we change two Words of the same Signification one for
another; which when one is better understood than the other, may
serve to discover what Idea the unknown stands for; but is very far
from a Definition, unless we will say, every English Word in the
Dictionary, is the definition of the Latin Word it answers, and that
Motion is a definition of Motus. Nor will the successive Application of
the parts of the Superficies of one Body, to those of another, which the
Cartesians give us, prove a much better definition of Motion, when
well examined.
Locke Hum III, 4, §9, p. 423