25. Extension being inseparable from body, proves it not the same.
It is true, the idea of extension joins itself so
inseparably with all visible, and most tangible qualities, that it suffers us to see no one, or feel very few external
objects, without taking in impressions of extension too. This readiness of extension to make itself be taken notice
of so constantly with other ideas, has been the occasion, I guess, that some have made the whole essence of body
to consist in extension; which is not much to be wondered at, since some have had their minds, by their eyes and
touch, (the busiest of all our senses,) so filled with the idea of extension, and, as it were, wholly possessed with it,
that they allowed no existence to anything that had not extension. I shall not now argue with those men, who take
the measure and possibility of all being only from their narrow and gross imaginations: but having here to do only
with those who conclude the essence of body to be extension, because they say they cannot imagine any sensible
quality of any body without extension,--I shall desire them to consider, that, had they reflected on their ideas of
tastes and smells as much as on those of sight and touch; nay, had they examined their ideas of hunger and thirst,
and several other pains, they would have found that they included in them no idea of extension at all, which is but
an affection of body, as well as the rest, discoverable by our senses, which are scarce acute enough to look into
the pure essences of things.
