For, when the ball obeys the motion of a billiard-stick, it is not any action of the ball, but bare passion.

Also when by impulse it sets another ball in motion that lay in its way, it only communicates the motion it had received from another, and loses in itself so much as the other received: which gives us but a very obscure idea of an ACTIVE power of moving in body, whilst we observe it only to TRANSFER, but not PRODUCE any motion.

For it is but a very obscure idea of power which reaches not the production of the action, but the continuation of the passion.

For so is motion in a body impelled by another; the continuation of the alteration made in it from rest to motion being little more an action, than the continuation of the alteration of its figure by the same blow is an action.

The idea of the BEGINNING of motion we have only from reflection on what passes in ourselves; where we find by experience, that, barely by willing it, barely by a thought of the mind, we can move the parts of our bodies, which were before at rest.