Amid the ongoing debate over the proper interpretation of Aristotle's theory of sense perception in the "De Anima," Steven Everson has recently presented a well-documented and ambitious treatment of the issue, arguing in favor of Richard Sorabji's controversial position that sense organs literally take on the qualities of their proper objects. Against the interpretation of M. F. Burnyeat, Everson and others make a compelling case the Aristotelian account of sensation requires some physical process to occur in sense organs. A detailed (...) examination of the interpretation by Everson and Sorabji of Aristotle's theory, however, shows that their reading cannot be the correct one, since it involves many textual and philosophical difficulties. Their interpretation, for instance, would require abandoning Aristotle's requirement that only a transparent substance is suitable matter for an eye. Likewise, their understanding of the Aristotle's doctrine of sensation as the reception of form without matter in "DA 2.12" cannot be reconciled with other texts of his from "On Generation and Corruption." An analysis of these texts, as well as "DA 2.7" and "De Sensu 6" on the roles of light and the transparent medium in vision, show that, for Aristotle, the physical processes which sense organs undergo are not standard qualitative changes (i.e. alterations), but activities or the actualizations of potencies in the material constituents of living animal bodies. (shrink)

This is a close scrutiny of De Anima II 5, led by two questions. First, what can be learned from so long and intricate a discussion about the neglected problem of how to read an Aristotelian chapter? Second, what can the chapter, properly read, teach us about some widely debated issues in Aristotle's theory of perception? I argue that it refutes two claims defended by Martha Nussbaum, Hilary Putnam, and Richard Sorabji: that when Aristotle speaks of the perceiver becoming like (...) the object perceived, the assimilation he has in mind is ordinary alteration of the type exemplified when fire heats the surrounding air, that this alteration stands to perceptual awareness as matter to form. Claim is wrong because the assimilation that perceiving is is not ordinary alteration. Claim is wrong because the special type of alteration that perceiving is is not its underlying material realisation. Indeed, there is no mention in the text of any underlying material realisation for perceiving. The positive aim of II 5 is to introduce the distinction between first and second potentiality, each with their own type of actuality. In both cases the actuality is an alteration different from ordinary alteration. Perception exemplifies one of these new types of alteration, another is found in the acquisition of knowledge and in an embryo's first acquisition of the power of perception. The introduction of suitably refined meanings of 'alteration' allows Aristotle to explain perception and learning within the framework of his physics, which by definition is the study of things that change. He adapts his standard notion of alteration, familiar from Physics III 1-3 and De Generatione et Corruptione I, to the task of accounting for the cognitive accuracy of perception and second potentiality knowledge: both are achievements of a natural, inborn receptivity to objective truth. Throughout the paper I pay special attention to issues of text and translation, and to Aristotle's cross-referencing, and I emphasise what the chapter does not say as well as what it does. In particular, the last section argues that the textual absence of any underlying material realisation for perceiving supports a view I have defended elsewhere, that Aristotelian perception involves no material processes, only standing material conditions. This absence is as telling as others noted earlier. Our reading must respect the spirit of the text as Aristotle wrote it. (shrink)