But some doubt arises when we consider the phenomena of hearing. Perhaps we are to understand the process thus: the air is modified by the first movement; layer by layer it is successively acted upon by the object causing the sound: it finally impinges in that modified form upon the sense, the entire progression being governed by the fact that all the air from starting point to hearing point is similarly affected. Perhaps, on the other hand, the intervenient is modified only by the accident of its midway position, so that, failing any intervenient, whatsoever sound two bodies in clash might make would impinge without medium upon our sense? Still air is necessary; there could be no sound in the absence of the air set vibrating in the first movement, however different be the case with the intervenient from that onwards to the perception point. The air would thus appear to be the dominant in the production of sound: two bodies would clash without even an incipient sound, but that the air, struck in their rapid meeting and hurled outward, passes on the movement successively till it reaches the ears and the sense of hearing. But if the determinant is the air, and the impression is simply of air-movements, what accounts for the differences among voices and other sounds? The sound of bronze against bronze is different from that of bronze against some other substance: and so on; the air and its vibration remain the one thing, yet the difference in sounds is much more than a matter of greater or less intensity. If we decide that sound is caused by a percussion upon the air, then obviously nothing turning upon the distinctive nature of air is in question: it sounds at a moment in which it is simply a solid body, until it is sent pulsing outwards: thus air in itself is not essential to the production of sound; all is done by clashing solids as they meet and that percussion, reaching the sense, is the sound. This is shown also by the sounds formed within living beings not in air but by the friction of parts; for example, the grinding of teeth and the crunching of bones against each other in the bending of the body, cases in which the air does not intervene. But all this may now be left over; we are brought to the same conclusion as in the case of sight; the phenomena of hearing arise similarly in a certain co-sensitiveness inherent in a living whole.

Timaeus: and the causes whereby its affections are produced. In general, then, let us lay it down that sound is a stroke transmitted through the...

Now what is it that makes the Hearing, that you can hear that which stirs and makes a Noise? Wilt thou say that it is caused by the Noise of that...

Timaeus: and that large motion produces “loud” sound, and motion of the opposite kind “soft” sound. The subject of concords of sounds must...

Timaeus: and have already fallen to a speed similar to that with which the slower sounds collide with them afterwards and move them; and when the...

Thus now the Habitation of Man's Sound, wherein the Understanding is, must be from Eternity, although indeed in the Fall of Adam, Man has set himself...

Namely, when we thus perceive by touch the warmth here in the body . And of it we have this audible proof: Namely, when we thus, after stopping our...

Timaeus: and the causes of deglutition, and of projectiles, whether discharged aloft or flying over the surface of the earth; and the causes also of...

Timaeus: since the particles do not transmit to one another the original affection, it fails to act upon the living creature as a whole, and the...

But where are the two? There is a second, I said, which is the counterpart of the one already named. And what may that be? The second, I said, would s...

Timaeus: not being derived either from many or from simple forms, but are indicated by two distinctive terms only, “pleasant” and “painful” of which...

Timaeus: the perturbable to the imperturbable; and that, through learning and sharing in calculations which are correct by their nature, by imitation...

"Well, then," enquired Tzŭ Yu, "since the music of earth consists of nothing more than holes, and the music of man of pipes and flutes,—of what...