The Concept of Identity.

White, Michael J.

Hirsch, Eli. Oxford: Oxford University Press, 1992 (paper). x + 318 pp. $16.95--Professor Hirsch's monograph on identity, which was first published in 1982, is now available (unaltered) in paperback. As the blurbs on the back cover of the paperback edition indicate, the book was widely (and favorably) reviewed at its first appearance. The work is an impressive one, usable in upper-division undergraduate or graduate seminars but with serious philosophical contributions to make. Hence, its republication in the less expensive paperback format is welcome.

From a "logistic" viewpoint, it may initially seem that identity is a relatively uninteresting relation: that relation which each thing bears to itself but not to anything else--that is, what Hume (in the Treatise) calls "unity." Of course, what such a perspective presupposes is that the "things in the domain of the relation" are already individuated or "identified." Here is the locus of philosophers' usual interest in identity. In particular, Hirsch is concerned with the identity or persistence of things through time. Like any other philosophical enterprise, Hirsch's has its basic presuppositions: his most important one is that to account for the "career" of a thing--in particular, a physical object--we begin with "object-stages" or temporal slices and proceed to an analysis of the "unity-making relationship which binds the successive stages of the career of a single persisting object" (p. 7). An assumption of such an approach seems to be that "identifying" an object-stage or demarcating it from its environment is relatively unproblematic--or, at least, not a matter of central concern for the present philosophical enterprise. Hirsch's position with respect to object-stages and objects seems to be fundamentally operational rather than epistemic or metaphysical (but for more on the epistemic issue, see Chapter 6). In discussing the adequacy of what he calls "persistence-free languages," he comments that the primary interest of such a "language is that it affords a vantage point which is outside our ordinary identity scheme, and from which, therefore, we can gain a deeper insight into the character of that scheme" (p. 150).

With respect to current philosophical discussions of identity, the sortalism-nonsortalism distinction seems to be constitutive of something like party lines. A sortalist maintains that the identity/persistence conditions of something must be relativized to what kind of thing it is; a nonsortalist eschews such relativization. Hirsch, in a sense, bridges this gap. He is a sortalist insofar as he holds that an adequate account of the grouping of object-stages into the career of a single, persisting "normal object" depends on reference to a sort or kind into which those object-stages fall. Moreover, what linguistic items are to count as sortals is not "independently" specifiable in syntactic or grammatical terms: it depends on whether the item in question in fact allows us "to trace a career" using it (to group a collection of object-stages into the "career of a single persisting object"). Hirsch does believe, however, that it is possible to specify some general features shared by sortals. He further believes that it is possible to get at our "most basic idea of the persistence of an object" (p. 80) by means of a sortal-neutral account of when a collection of object-stages constitute a career of a single persisting object. This account appeals to spatiotemporal and qualitative continuity and what Hirsch terms "minimization of change." The upshot is that Hirsch rejects what he terms the extreme position of Wiggins et al., according to which "our concept of persistence is at its very roots dependent upon sortal differentiations" (p. 73). Finally, Hirsch finds compelling a view according to which, in the case of matter, as opposed to "familiar articulated objects," there is some ultimate and unobservable relationship ("genidentity") "which binds the successive stages into a bit of matter" (p. 121).

Part 1 of the book is largely devoted to a careful analysis of the persistence of objects in the terms that I have discussed. In part 2 Hirsch discusses related issues, including personal identity, in largely self-contained chapters. One of many suggestions in Part Two is that "our minds are innately determined to synthesize the stages" constitutive of "ordinary objects" into those objects (p. 179). As earlier reviewers correctly indicated, Hirsch's book is marked by its clarity and carefulness of argumentation and its general sensibleness. Now that it is available in paperback, it is a book that philosophers will want to consider for use in mid-level and advanced courses.