— 178 —
Extension being inseparable from Body, proves it not the same.       §24. ’Tis true, the Idea of Extension joins it self 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 it self 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 wond’red 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 any thing, 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 Exten-
sion, 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,
— 179 —
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.
Locke Hum II, 13, §24, pp. 178-179