Sound always comes from motion. Wherever there is motion, two things are meeting, if only a thing of weight and space.

Sound, however, in its most customary meaning, can be seen as coming from the meeting of two things of weight: the meeting implies motion.

A stone falls on some flat wood. A sound occurs. The stone has changed the wood—for example, by denting it, or making some splinters. The wood has done something to the stone, though this is less perceptible.

The sound of the stone falling on the wood can be seen as apart from what happens to the stone and wood, and also from the fact that the stone has changed its position in space, and to a slight degree—for the wood has “gone down a little”—the wood has. Sound is “what else” has happened.

It is possible that the flat wood could have been raised while the stone was falling. The two objects meeting would then both have been in definite motion.

Sounds have shape and time and energy and size in them. For example, the shape of the stone would have something to do with the sound it made meeting the wood. The time the stone took in falling would have something to do with it. (This takes in the problems of slowness and speed.) The stone here was not thrown, but it might have been; however, since the time a stone has been falling has to do with energy, energy can also be seen as having to do with the specific sound. Had the stone been thrown, a new important phase of energy would have come to exist. And then the size, in terms of the stone’s dimensions and of its weight, had to do with the sound. Sound is an instantaneous composition of forms or possibilities of the universe.