ABSTRACT
Most Neoplatonists were convinced that the perceptual activity of the senses is a conscious activity, including even the reception of primary sense-qualities such as colours and sounds. is means that we cannot perceive anything unless we are aware of the speci c impact exerted by the sense-object upon the sense-organ. e commentators can also rely on the doctrine found in Aristotle’s Physics 7.2, according to which what is distinctive of perceptual alterations is that the subject is aware of them.1 e problem with that discussion was that it did not explain why some alterations rather than others involve awareness. Why are we supposed to think that sense-perception implies awareness whereas other forms of qualitative change do not? For this reason, the discussion seemed to leave mysterious the possession by the sense-organs of the capacity to perceive. Moreover, an important part of the awareness involved in sense-perception is that we are aware not only of the speci c impact, but also of the perceptual activity of our sensory power. e root of the problem is exposed in Aristotle’s de Anima. In 3.2, Aristotle insists that we do perceive that we perceive. He seems to take it for granted that our perceptual system is capable of grasping its own operations. At the beginning of de Anima 3.2, he presents the following aporia:
Since we perceive that we see and hear, it must either be by sight that one perceives that one sees or by another [sense]. But in that case there will be the same [sense] for sight and the colour which is the subject for sight – so that either there will be two senses for the same thing or {the sense} itself will be the one for itself. (425b12-16, trans. Hamlyn)2
e distinction between perception and perception of perception – perceptual consciousness – is here taken for granted, and the fact that a subject perceives that he perceives is something that calls for explanation. In principle, the problem posed by Physics 7.2 is now resolved. On the account of the de Anima, in order for the subject to be aware of
a perceptual alteration, he has to exercise the full capacity for sense-perception which includes the working of both the particular sense in question and the perceptual system as a whole. It implies that not only are the particular sense-organs altered by their proper objects but that the central sense, located in the heart, is also working. Perception of external sense-objects is not the same as perceptual awareness but, as is clear from Aristotle’s explanation of insensitivity in sleep, it requires it (see de Somno 2.455a33-b1, b8-12). If the controlling sense-organ, and hence the common perceptual power, is not operative, the particular senses will not be capable of getting activated either. Although the organ of touch, for instance, will presumably still have the capacity to be heated and cooled when the subject is asleep, such changes do not produce perception because the subject temporarily lacks the capacity to perceive his perceptions. e possession of this capacity depends not on the condition of the particular sense-organs but on that of the central organ, the heart, which controls the entire process at the level of physiology as well. On the other hand, Aristotle also raises the possibility that it is the same particular sense that is capable of perceiving both its primary objects and the act of perceiving them.
