BOOK I PART II
reasonings on the present subject, and makes
it almost impossible to answer in an intelligi-
ble manner, and in proper expressions, many
questions which may arise concerning it.
III. There have been many objections drawn
from the mathematics against the indivisibil-
ity of the parts of extension: though at first
sight that science seems rather favourable to
the present doctrine; and if it be contrary in
itsdemonstrations, it is perfectly conformable
in its definitions. My present business then
must be to defend the definitions, and refute
the demonstrations.
A surface isdefinedto be length and breadth
without depth: A line to be length without
breadth or depth: A point to be what has nei-
ther length, breadth nor depth. It is evident
that all this is perfectly unintelligible upon any