Online research in philosophy

This paper explores the relationship between psychology and neurobiology in the context of cognitive science. Are the sciences that constitute cognitive science independent and theoretically autonomous, or is there a necessary interaction between them? I explore Fodor's Multiple Realization Thesis (MRT) which starts with the fact of multiple realization and purports to derive the theoretical autonomy of special sciences (such as psychology) from structural sciences (such as neurobiology). After laying out the MRT, it is shown that, on closer inspection, the argument is either circular or self-undermining--the argument either assumes the very autonomy it seeks to demonstrate or the concluded autonomy is contradicted by the theoretical interdependence invoked by the premises of the argument. Next, I explore a concrete example of multiple realization in the explanation of animal behavior: the convergent evolution of jamming avoidance behaviors in three genera of weakly electric fish. Contrary to the image painted by the MRT, the work on these animals involves a high degree of interaction between the various levels of investigation. The fact that our understanding of electric fish behavior involves functional theories and multiple realization without the kind of disunified science that is supposed to follow from such a situation indicates that the mere fact of multiple realization cannot be the basis for an autonomous psychology.

The reigning picture of special sciences, what we will term the ‘received’ view, grew out of the work of writers, such as Jerry Fodor, William Wimsatt, and Philip Kitcher, who overturned the Positivist’s jaundiced view of these disciplines by looking at real cases from the biological sciences, linguistics, psychology, and economics, amongst other areas.¹ Central to the received view is the ontological claim that the ‘multiple realization’ of properties is widespread in the special sciences which we may frame thus.

One trend in recent work on topic of the multiple realization of psychological properties has been an emphasis on greater sensitivity to actual science and greater clarity regarding the metaphysics of realization and multiple realization. One contribution to this trend is Bechtel and Mundale’s examination of the implications of brain mapping for multiple realization. Where Bechtel and Mundale argue that studies of brain mapping undermine claims about the multiple realization, this paper challenges that argument.

Multiple realizability has been at the heart of debates about whether the mind reduces to the brain, or whether the items of a special science reduce to the items of a physical science. I analyze the two central notions implied by the concept of multiple realizability: "multiplicity," otherwise known as property variability, and "realizability." Beginning with the latter, I distinguish three broad conceptual traditions. The Mathematical Tradition equates realization with a form of mapping between objects. Generally speaking, x realizes (or is the realization of) y because elements of y map onto elements of x. The Logico-Semantic Tradition translates realization into a kind of intentional or semantic notion. Generally speaking, x realizes (or is the realization of) a term or concept y because x can be interpreted to meet the conditions for satisfying y. The Metaphysical Tradition views realization as a species of determination between objects. Generally speaking, x realizes (or is the realization of) y because x brings about or determines y. I then turn to the subject of property variability and define it in a formal way. I then conclude by discussing some debates over property identity and scientific theory reduction where the resulting notion of multiple realizability has played a central role, for example, whether the nonreductive consequences of multiple realizability can be circumvented by scientific theories framed in terms of narrow domain-specific properties, or wide disjunctive properties.

It is widely held that disciplines are autonomous when their taxonomies are “substrate neutral” and when the events, states and processes that realize their descriptive vocabulary are heterogeneous. This will be particularly true in the case of disciplines whose taxonomy consists largely in terms that individuate by function. Having concluded that the multiple realization of functional kinds is far less widespread than assumed or argued for, Shapiro cannot avail himself of the argument for the autonomy of the special sciences which relies on multiple realization. This makes urgent the question of whether we must “now give up the idea that functionalist taxonomies have any scientific value?” [p. 650]. He acknowledges that we must either deny that the special sciences are autonomous, because higher level kinds have only a single realization and can thus be reduced, or else we must deny that there are empirical laws in the special sciences. “In other words, either special sciences have no ontological independence from lower level sciences or, worse, they have no empirical laws, which is to say that they are not empirical sciences at all. [p. 650]” Shapiro’s reductionist/eliminativist dilemma for the special sciences is unreal. For he has not canvassed the most important source of multiple realization in nature, and this source obviates his dilemma for most of the special sciences. Moreover, the route he offers between the horns of his dilemma leads pretty directly to impalement on its eliminativist horn. Or so I shall try to show in this comment.

ABSRACT: An increasing number of writers (for example, Kim ((1992), (1999)), Bechtel and Mundale (1999), Keeley (2000), Bickle (2003), Polger (2004), and Shapiro ((2000), (2004))) have attacked the existence of multiple realization and wider views of the special sciences built upon it. We examine the two most important arguments against multiple realization and show that neither is successful. Furthermore, we also defend an alternative, positive view of the ontology, and methodology, of the special science. In contrast to the claims of recent critics, we show that methodological connections between the neurosciences and psychology are plausibly often the result of multiple realization.

Thomas Polger and Laurence Shapiro argue that Carl Gillett's much publicized dimensioned theory of realization is incoherent, being subject to a reductio. Their argument turns on the fact that Gillett's definition of realization makes property instances the exclusive relata of the realization relation, while his belief in multiple realization implies its denial, namely, that properties are the relata of the realization relation on occasions of multiple realization. Others like Sydney Shoemaker have also expressed their view of realization in terms of property instances, yet they too have accepted the multiple realizability of properties. Thus I am interested in the more general issue raised by Polger and Shapiro's argument. Specifically, I show how to supplement a theory of realization with a category-inclusive auxiliary assumption, which avoids the stated reductio. I then offer a few reasons to justify the proposed category-inclusive view of realization, making some comparisons to supervenience and causation along the way.

Forthcoming in Philosophy of Science. Despite some recent advances, multiple realization remains a largely misunderstood thesis. Consider the dispute between Lawrence Shapiro and Carl Gillett over the application of Shapiro’s recipe for deciding when we have genuine cases of multiple realization. I argue that Gillett follows many philosophers in mistakenly supposing that multiple realization is absolute and transitive. Both of these are problematic. They are tempting only when we extract the question of multiple realization from the explanatory context in which it is invoked. Anchoring multiple realizability in its theoretical context provides grounds for arbitrating disagreements. Doing so, I argue, favors the view advanced by Shapiro.

Carl Gillett has defended what he calls the “dimensioned” view of the realization relation, which he contrasts with the traditional “flat” view of realization (2003, 2007; see also Gillett 2002). Intuitively, the dimensioned approach characterizes realization in terms of composition whereas the flat approach views realization in terms of occupiers of functional roles. Elsewhere we have argued that the general view of realization and multiple realization that Gillett advances is not able to discharge the theoretical duties of those relations (Shapiro 2004, unpublished manuscript; Polger 2004, 2007, forthcoming). Here we focus on an internal objection to Gillett’s account and then raise some broader reasons to reject it.