BOOK I PART II
spond to each other, and to any common mea-
sure, with which they are compared, we form
a mixed notion of equality derived both from
the looser and stricter methods of comparison.
But we are not content with this. For as sound
reason convinces us that there are bodies vastly
more minute than those, which appear to the
senses; and as a false reason would perswade
us, that there are bodies infinitely more minute;
we clearly perceive, that we are not possessed
of any instrument or art of measuring, which
can secure us from ill error and uncertainty.
We are sensible, that the addition or removal
of one of these minute parts, is not discernible
either in the appearance or measuring; and as
we imagine, that two figures, which were equal
before, cannot be equal after this removal or
addition, we therefore suppose some imagi-
nary standard of equality, by which the ap-