Force in potency is infinite, and the weight is finite. The movers, together with their moved body, are of two different powers: the first is when the mover is of less power than its moved body; the second when the mover is more powerful than its moved body, by itself in itself, without their application or other means. By as much as the mover is of less power than its moved body, by so much will it make a longer motion. By as much as the mover is more powerful than its moved body, by so much will it make a shorter motion. In these two propositions is understood the excess of an instant and no greater, for with the imagination you could proceed infinitely. By as much as the power of the mover exceeds more than is required to move its moved body, by so much can it be faster, being moved by the natural course of gravity.

Define then of power and resistance, which is treatable by means of the balance. The powers apt to give motion within movers are caused by three different causes, of which the first is causal, the others are caused by it. The causal is found in animate bodies, and the caused in animate and inanimate bodies. And that which is found in animate bodies is a power that moves of itself; and that power which moves of itself is the principle of the motion of the movable parts of such a body, by means of the congregation and disgregation of their particles. The second and third retain the nature of their causer, for although they are infused into insensible bodies -- which by this are drawn with a curving-away from their natural straightness -- nonetheless, just as from scarcity and abundance oppositely situated, they are generated in equal time. The scarcity and abundance which, born in equal time, are oppositely situated, are those that cause force in dense bodies, which with a curving-away are removed from their natural straightnesses. The scarcity and abundance, born in equal time in those dense bodies which with a curving-away by the animate power are removed from their natural straightness ... Dense bodies, which with a curving-away are removed from their natural straightness, in every degree of motion will acquire degrees of motive power, which ...

Go on subdividing always to the very last. Motions are of three kinds. The one: the mover does not part the moved body from its place, but rather turns it about. The other: the moved body and the mover always change place; sometimes they divide and sometimes they remain always united. The journeys of movers and moved bodies are of two kinds, of which in the first the mover and the motion go in one same direction; in the second, the mover goes opposite to its moved body. Sometimes the mover goes and returns while the moved body moves along one same path, and so conversely. Sometimes the mover goes in one direction only while the moved body goes and returns; and this happens in curved motions as in straight and in mixed of curved and straight. The curved and straight journeys of movers and their moved bodies are of two natures, of which in the first the moved body follows the journey of its mover; in the second, the moved body moves in contrary motion to that of its mover. Again the straight and curved motions can be varied together in two ways: sometimes the mover goes and returns while the moved body goes in one direction only; sometimes the mover goes in one direction only while the moved body goes and returns. Sometimes such movers and moved body make such effects without any means, and sometimes with a single or several intermediaries.

Immediately.

By means of, with the intermediary.

With an intermediary.

Immediately, and there are no more.

Sometimes the mover is of slow motion and the moved body of very long motion; sometimes the motion of the mover is long and that of the moved body very short. Sometimes the mover is slow and the moved body is fast; sometimes on the contrary, that is, the mover is fast and the moved body very slow. Sometimes the weak moved body makes almost resistance to the most powerful mover, and so conversely. Sometimes the moved body exchanges into the mover and the mover into the moved body; and this is by means of position. There are some motions of moved bodies that proceed at length after the end of the motion of their movers; and this can happen in straight motions as in circular. There are motions made by movers and moved bodies, straight and circular, which extend as far as that of their movers.

Motions and movers are sometimes along one same straightness; sometimes the mover will be lying level and the moved body perpendicular; sometimes the opposite; sometimes oblique; sometimes curved and inc[lined] ... Both the two are incorporeal, that is the animate power and the force; the third is the weight, which has body. The causal motive power and one of the two caused are incorporeal powers; the third is corporeal, because it creates the ...