This collection of 21 essays explores the creative interaction among the cognitive neurosciences, philosophy, and theology. It is the result of an international research conference co-sponsored by the Vatican Observatory, Rome, and the Center for Theology and the Natural Sciences, Berkeley.

Physicalism ? or roughly the view that the stuff that physics talks about is all the stuff there is ? has had a popular press in philosophical circles during the twentieth century. And yet, at the same time, it has become quite fashionable lately to believe that the mind matters in this world after all and that psychology is an autonomous science irreducible to physics. However, if (true, downward) mental causation implies non-reducibility and Physicalism implies the converse, it is hard (...) to see how these two views could be compatible. This paper reviews some classical arguments purportedly showing how the autonomy of the special sciences can be upheld without violating the laws of physics or the principle that physics constitutes a complete and closed system. These arguments are presented in order of increasing strength, indicating how the more popular arguments in fact fall short of establishing anti-reductionism of the intended kind. New arguments are added which claim to demonstrate quite effectively how downward causation is possible compatibly with the reign of physics. The paper begins with a section which distinguishes various kinds of reductionism. (shrink)

This paper critically examines the argument structure of Fodor's theory of modularity. Fodor claims computational autonomy as the essential properly of modular processing. This property has profound consequences, burdening modularity theory with corollaries of rigidity, non-plasticity, nativism, and the old Cartesian dualism of sensing and thinking. However, it is argued that Fodor's argument for computational autonomy is crucially dependent on yet another postulate of Fodor's theory, viz. his thesis of strong modularity, ie. the view that functionally distinct modules must also (...) have physical counterparts in the neural architecture of the brain. Yet, Fodor offers little or no independent support for this neurological speculation. Moreover, due to the cognitivist underpinnings of Fodor's theory his view of modules as 'mental organs'faces an untenable dilemma that is to be traced back to the earliest history of modem cognitive science, viz. to the rationalist-computationalist research program initiated by Descartes and Male-branche. The tension characteristic for the Cartesian program was one that arose between information correlation and information processing accounts of the transactions between body and mind. Similarly, the tension characteristic for Fodor's theory of modularity is one between a causal account of modules on the model of simple detection mechanisms, and an information processing account of modules on the model of vast and elaborate cognitive systems. It is argued that the resulting concept of a cognitive module Fodorian style constitutes an amalgam of incompatible desiderata that fails to stake out a natural kind for cognitive science. As an alternative account, the final section shows connectionism to be capable of encompassing both Gibsonian and 'new look' accounts of cognitive achievements within one theoretical perspective, thus providing a fruitful interfield theory capable of combining the theoretical resources of the ecological approach with the indispensable theoretical complement provided by psychological processing accounts. This change of perspective would ultimately involve recasting the symbo-functionalist notion of cognitive function along bio-psychological lines. (shrink)

Theo C. Meyering, in “Mind Matters: Physicalism and the Autonomy of the Person,” takes yet a third approach to the issue of reduction. He states that “if (true, downward) mental causation implies nonreducibility [as Stoeger and Murphy argue] and physicalism implies the converse, it is hard to see how these two views could be compatible.” Meyering distinguishes three versions of reductionism: radical (industrial strength) physicalism; ideal (regular strength) physicalism, and mild or token physicalism. Radical physicalism asserts that all special sciences (...) are reducible to physics in the sense that their laws can be deduced via bridge laws from those of physics. Ideal physicalism asserts that while it is practically impossible to reduce the special sciences, such reduction would be possible were there an ideally complete physics" (Note: This distinction parallels Stoeger’s recognition that epistemological reducibility is relative to the meaning of “laws of nature). Token physicalism is ontologically reductionist: there are no events that are not “token-identical” with some physical event or other (Note: See above, sec. 3.3). However, there are no identities between higher-level and lower- level types of events; consequently some events described by the special sciences have no physical explanation at all. -/- All of these reductionist positions are to be contrasted with compositional (milder than mild) physicalism, which asserts that some higher-level events are not even token-identical with physical events because the higher-level event (say, a crash in the stock market) is constituted by innumerable physical particulars in all sorts of states and interactions. -/- Meyering then surveys some of the existing arguments for the nonreducibility of the special sciences. One of the most important is the argument from multiple realizability. The claim is that economics, for example, is not reducible to physics because economic concepts (for example, monetary exchange) are “wildly multiply realizable” (for example, using coins, strings of wampum, signing a check). Thus, there can be no bridge laws and no reduction. Such an argument, however, only cuts against radical physicalism, not the weaker (and a priori more plausible) ideal physicalism. -/- A stronger argument for the indispensability of special-science explanations is based on the role of functional explanations. For example, the functional description of aspirin as an analgesic is in some instances a more useful explanation of its causal role (relieving a headache) than is its description as the chemical level. -/- Meyering’s own contribution focuses neither on multiple realizability of supervenient properties nor on multiple “fillers” of functional roles, but on “multiple supervenience.” In particular, a single subvenient state of affairs (for example, a cloud of free electrons permeating the metal of which a ladder is constructed) may realize a variety of supervenient dispositional properties (in this case, electrical conductivity, thermal conductivity, opacity). An explanation (say, of the cause of a deadly accident) requires reference to the dispositional property (electrical conductivity), not merely to the subvenient property. Meyering argues that it is this possibility of multiple supervenience, not multiple realizability, that gives arguments against reduction based on functional properties their real force. Downward causation, then, can be understood in terms of selective activation of one of several dispositional properties of a lower-level state, and thus can be assigned a stable place in our picture of how the world is organized without upsetting our conception of physics as constituting a closed and complete system of physical events. (shrink)