BOOK I PART II
nothing, and never receives the idea of exten-
sion, nor indeed any idea, from this invariable
motion. Even supposing he moves his limbs to
and fro, this cannot convey to him that idea. He
feels in that case a certain sensation or impres-
sion, the parts of which are successive to each
other, and may give him the idea of time: But
certainly are not disposed in such a manner, as
is necessary to convey the idea of space or the
idea of space or extension.
Since then it appears, that darkness and mo-
tion, with the utter removal of every thing vis-
ible and tangible, can never give us the idea of
extension without matter, or of a vacuum; the
next question is, whether they can convey this
idea, when mixed with something visible and
tangible?
It is commonly allowed by philosophers,