NATURE OF THE GROUNDWORK OF SCIENCE 307

imagine nothing except ^vhat our senses have previously

experienced either as a whole or in its constituent parts.

This close connexion between experience and imagination

has for its consequence the following law of association :

Facts of experience are reproduced in our imagination

with the greater ease and readiness the more frequently

or continuously they have been experienced by us.

But we have just seen* how movements of solid bodies

constitute the most constant and universal of all our

experiences. What wonder, then, that a sense of ease and

pleasurable relief should be felt whenever difficult and

puzzling phenomena of any kind can be presented to the

intellect in terms and by the aid of mental images of

moving solid bodies.

It should also be recollected that few things are more

familiar to us than the experience that objects of considerable

size can mostly be broken, cut, or crushed by us into smaller

portions, and these again similarly further subdivided. It

is a most common experience also to see substances crushed

into very small particles (sand, dust, or what not) particles so

small that we are unable to subdivide them any further.

Hence a vague feeling can be produced of a distinctness

in nature between large bodies we can subdivide and

possessing obvious qualities, and minute particles which we

cannot so act upon, and of which we can detect hardly any

qualities particles only just within the range of our vision.

In this way an imagination easily and spontaneously arises

of large bodies being made up of minute solid particles

incapable of smaller subdivision which, by their union and

coherence, compose such bodies.

Through a combination of these multitudinous and con-

tinual experiences, the tendency has arisen (probably ages

before Democritus), still exists, and will, most likely, ever

* See ante, p. 302.

imagine nothing except ^vhat our senses have previously

experienced either as a whole or in its constituent parts.

This close connexion between experience and imagination

has for its consequence the following law of association :

Facts of experience are reproduced in our imagination

with the greater ease and readiness the more frequently

or continuously they have been experienced by us.

But we have just seen* how movements of solid bodies

constitute the most constant and universal of all our

experiences. What wonder, then, that a sense of ease and

pleasurable relief should be felt whenever difficult and

puzzling phenomena of any kind can be presented to the

intellect in terms and by the aid of mental images of

moving solid bodies.

It should also be recollected that few things are more

familiar to us than the experience that objects of considerable

size can mostly be broken, cut, or crushed by us into smaller

portions, and these again similarly further subdivided. It

is a most common experience also to see substances crushed

into very small particles (sand, dust, or what not) particles so

small that we are unable to subdivide them any further.

Hence a vague feeling can be produced of a distinctness

in nature between large bodies we can subdivide and

possessing obvious qualities, and minute particles which we

cannot so act upon, and of which we can detect hardly any

qualities particles only just within the range of our vision.

In this way an imagination easily and spontaneously arises

of large bodies being made up of minute solid particles

incapable of smaller subdivision which, by their union and

coherence, compose such bodies.

Through a combination of these multitudinous and con-

tinual experiences, the tendency has arisen (probably ages

before Democritus), still exists, and will, most likely, ever

* See ante, p. 302.