perception without its matter ; and this accounts for impressions and images being still present in the sentient organs, after objects have been withdrawn.
The action of the object of perception is one and the same with that of the sense, although they differ in mode of being—I mean, for example, sound in action and hearing in action ; for it may be that an individual, endowed with hearing, does not hear, as that a sonorous body does not give out sound. But when an individual, capable of hearing, listens, and when that which is sonorous gives out sound, then hearing in action coincides with sound in action, and the one may strictly be termed hearing, the other sound. If motion, production, and impression, are in the product, it follows that sound and hearing, in an active state, must pre-exist in hearing in a potential state; for the action of the creative and the motive exists, naturally, in that which is to be acted upon. It is, therefore, no way necessary that the motor should be itself in motion. The action, then, of the sonorous body is sound or sounding, that of the auditory sense is hearing or audition; for hearing is double as sound is double, and the same applies to other senses and perceptions. Since production and impression are, not in that which acts but, in that which is impressed, so the action of the object of perception and the sensibility is in the sentient being. But, while for some senses these two states have
