Hume Studies

Hume Studies Volume XXI, Number 1, April 1995, pp. 117-133 Hume, Images and Abstraction SONIA SEDIVY Hume's account of general or abstract ideas proposes that mental images can serve as the means for general thought by virtue of their functional role. More interesting than its sophistication, however, is the fact that the account fails in an illuminating way. Though I will explain Hume's theory by locating it in the debate over general ideas to which it was a response, the critical examination presented here is relevant to any attempt to base an account of mental representation exclusively on mental images and their deployment.1 Since Hume conceived the problem of general ideas as that of how individual items can become "general in their representation,"2 his theory speaks to contemporary enquiries into the nature of mental representation. Hume's immediate concern was "whether [abstract or general ideas] be general or particular [determinate] in the mind's conception of them" (T 17).3 In more modern terminology, Hume's question was this: how can individual mental representations, which of course have a determinate character, bear general contents or be general in what they represent, namely groups of objects? In representing a group of objects, a general idea conveys the commonality by virtue of which the members are similar or "hang together."4 If, like Hume, one operates with the background assumption that mental items represent by virtue of their intrinsic character, it is puzzling how an item having a determinate intrinsic character could be general in its representing. Hume regarded previous discussions as having structured the debate so as to give the appearance of a dilemma, both horns of which failed to explain Sonia Sedivy is at Scarborough College and the Department of Philosophy, 215 Huron Street, University of Toronto, Toronto, Ontario M5S IAl, Canada, email: sedivy@lake.scar.utoronto.ca 118 Sonia Sedivy how determinate items might stand for general ideas. It had come to seem that general representing may be accomplished only in one of two possible ways, as Hume wrote, "either by representing at once all possible sizes and all possible qualities, or by representing no particular one at all" (T 18). In other words, it seemed that general representing might be accomplished either by a set of determinate items where each represents a particular instance of the complete comprehension of the general idea,5 or by a single determinate item which does not pick out any determinate quantities or qualities at all. The first option is not viable since the mind is finite, while the second is simply mysterious . How could items that manage to represent by virtue of their intrinsic characteristics nevertheless be representing "no particular [quantity] at all"? Hume rejected the dilemma, claiming that the two unsatisfactory options—that mental items must represent all determinate instances or nothing determinate at all—are not exhaustive. He found the basis for a third option in Berkeley's insight that what a mental item represents might be determined by the way it is used in reasoning rather than just by its intrinsic character. Berkeley proposed that representationality is a matter of the relation a representing item bears to what it represents and that mental items can stand in representational relations by virtue of the way they are used in thought, particularly in reasoning or "demonstration." If a representing item is used in reasoning in such a way that it could stand for any one of a number of different individual members of a group "indifferently" then it represents the group in general.6 In essence, Berkeley's insight is that determinate mental items need not represent by virtue of their intrinsic characteristics, but rather by virtue of further facts about their place in the cognitive economy. Hume elaborates Berkeley's approach in the terms of his strictly empiricist and mechanistic associationist framework. Thus Hume conceives of the mind as a "collection of different perceptions, united together by certain relations" (T 207). That is, the only "furnishings" allowed in Hume's account of mind are image-like sensory impressions and copies thereof. These furnishings are linked associatively, such that certain intrinsic qualities of images produce associations...