the powers of gravity, specific attraction,
electricity, magnetism, and even the spirit of animation, may consist of
matter of a finer kind; and to believe, with St. Paul and Malbranch, that
the ultimate cause only of all motion is immaterial, that is God. St. Paul
says, "in him we live and move, and have our being;" and, in the 15th
chapter to the Corinthians, distinguishes between the psyche or living
spirit, and the pneuma or reviving spirit. By the words spirit of animation
or sensorial power, I mean only that animal life, which mankind possesses
in common with brutes, and in some degree even with vegetables, and leave
the consideration of the immortal part of us, which is the object of
religion, to those who treat of revelation.

II. 1. _Of the Sense of Touch._

The first idea we become acquainted with, are those of the sense of touch;
for the foetus must experience some varieties of agitation, and exert some
muscular action, in the womb; and may with great probability be supposed
thus to gain some ideas of its own figure, of that of the uterus, and of
the tenacity of the fluid, that surrounds it, (as appears from the facts
mentioned in the succeeding Section upon Instinct.)

Many of the organs of sense are confined to a small part of the body, as
the nostrils, ear, or eye, whilst the sense of touch is diffused over the
whole skin, but exists with a more exquisite degree of delicacy at the
extremities of the fingers and thumbs, and in the lips. The sense of touch
is thus very commodiously disposed for the purpose of encompassing smaller
bodies, and for adapting itself to the inequalities of larger ones. The
figure of small bodies seems to be learnt by children by their lips as much
as by their fingers; on which account they put every new object to their
mouths, when they are satiated with food, as well as when they are hungry.
And puppies seem to learn their ideas of figure principally by the lips in
their mode of play.

We acquire our tangible ideas of objects either by the simple pressure of
this organ of touch against a solid body, or by moving our organ of touch
along the surface of it. In the former case we learn the length and breadth
of the object by the quantity of our organ of touch, that is impressed by
it: in the latter case we learn the length and breadth of objects by the
continuance of their pressure on our moving organ of touch.

It is hence, that we are very slow in acquiring our tangible ideas,