attributed to motion?

HYL. It may.

PHIL. It is then good sense to speak of MOTION as of a thing that is
LOUD, SWEET, ACUTE, or GRAVE.

HYL. _I_ see you are resolved not to understand me. Is it not evident
those accidents or modes belong only to sensible sound, or SOUND in the
common acceptation of the word, but not to sound in the real and
philosophic sense; which, as I just now told you, is nothing but a
certain motion of the air?

PHIL. It seems then there are two sorts of sound--the one vulgar, or
that which is heard, the other philosophical and real?

HYL. Even so.

PHIL. And the latter consists in motion?

HYL. I told you so before.

PHIL. Tell me, Hylas, to which of the senses, think you, the idea of
motion belongs? to the hearing?

HYL. No, certainly; but to the sight and touch.

PHIL. It should follow then, that, according to you, real sounds may
possibly be SEEN OR FELT, but never HEARD.