Paul Davies

This dissertation is concerned with two general issues. A theory of functional or teleological properties, as possessed by natural objects, grounded in the theory of evolution by natural selection. This I refer to as the evolutionary theory of functions. A cluster of theories in philosophy of mind which attempt to explicate intentionality--the representational powers of mental phenomena--in terms of evolutionary functions. ;The aim of this dissertation is threefold. To develop a version of the evolutionary theory of functions in which the proper role of evolution by natural selection is made fully explicit. To defend two theses in philosophy of biology, namely that the evolutionary theory of functions, when properly articulated, cannot justify the attribution of malfunctions to any natural objects, and that the evolutionary theory of functions justifies the attribution of evolutionary functions only to those organismic traits that directly causally engage the relevant selective demands, and hence does not justify the attribution of any evolutionary functions to paradigmatically functional traits such as hearts, kidneys, etc. To defend two analogous these in philosophy of mind, namely that the evolutionary theory of functions, insofar as it cannot account for malfunctions, cannot account for misrepresentations , and that the evolutionary theory of functions warrants the attribution of evolutionary functions to just those effects of the mind which directly engage the organism with its environment, but not to those mechanisms or states of the mind concerned with representational contents. ;A secondary aim is to argue that the most developed view of evolutionary functions in the recent literature--a view presented in Millikan --is inadequate on internal grounds. ;The general conclusion of the dissertation is twofold. First, the evolutionary theory of functions is restricted in surprising ways; this is an important result in philosophy of biology. Second, and as a consequence of the first, the evolutionary theory of functions is of no avail in theories of intentionality; this is an important result in philosophy of mind

Teleosemantics asserts that mental content is determined by natural selection. The thesis is that content is fixed by the historical conditions under which certain cognitive mechanisms—those that produce and those that interpret representational states—were selectively successful. Content is fixed by conditions of selective success. The thesis of this paper is that teleosemantics is mistaken, that content cannot be fixed by conditions of selective success, because those conditions typically outnumber the intentional objects within a given representational state. To defend against this excess, advocates of teleosemantics must attempt to privilege some conditions of success while ignoring others. This results in selective explanations that are ad hoc, thereby depriving teleosemantics of the virtues it hoped to inherit from the theory of evolution by natural selection, including its alleged naturalistic credentials.

Fred Dretske asserts that the conscious or phenomenal experiences associated with our perceptual states—e.g. the qualitative or subjective features involved in visual or auditory states—are identical to properties that things have according to our representations of them. This is Dretske's version of the currently popular representational theory of consciousness . After explicating the core of Dretske's representational thesis, I offer two criticisms. I suggest that Dretske's view fails to apply to a broad range of mental phenomena that have rather distinctive subjective or qualitative features. I also suggest that Dretske's view, in identifying conscious experiences with features of our perceptual states, casts its aim too low. It deflates further than it should and, in consequence, fails to capture what are arguably some of the most important phenomena associated with our conscious lives

The social exchange theory of reasoning, which is championed by Leda Cosmides and John Tooby, falls under the general rubric “evolutionary psychology” and asserts that human reasoning is governed by content-dependent, domain-specific, evolutionarily-derived algorithms. According to Cosmides and Tooby, the presumptive existence of what they call “cheater-detection” algorithms disconfirms the claim that we reason via general-purpose mechanisms or via inductively acquired principles. We contend that the Cosmides/Tooby arguments in favor of domain-specific algorithms or evolutionarily-derived mechanisms fail and that the notion of a social exchange rule, which is central to their theory, is not correctly characterized. As a consequence, whether or not their conclusion is true cannot be established on the basis of the arguments they have presented.

Much of the modern period was dominated by a `reductionist' theory of science. On this view, to explain any event in the world is to reduce it down to fundamental particles, laws, and forces. In recent years reductionism has been dramatically challenged by a radically new paradigm called `emergence'. According to this new theory, natural history reveals the continuous emergence of novel phenomena: new structures and new organisms with new causal powers. Consciousness is yet one more emergent level in the natural hierarchy. Many theologians and religious scholars believe that this new paradigm may offer new insights into the nature of God and God's relation to the world. This volume introduces readers to emergence theory, outlines the major arguments in its defence, and summarizes the most powerful objections against it. Written by experts but suitable as an introductory text, these essays provide the best available presentation of this exciting new field and its potentially momentous implications.

A persistent boast of the historical approach to functions is that functional properties are normative. The claim is that a token trait retains its functional status even when it is defective, diseased, or damaged and consequently unable to perform the relevant task. This is because historical functional categories are defined in terms of some sort of historical success -- success in natural selection, typically -- which imposes a norm upon the performance of descendent tokens. Descendents thus are supposed to perform the associated task even when they cannot. The conceit, then, is that malfunctions are explicable in terms of historical success. The aim of this paper is to challenge this conceit. My thesis is that the historical approach to functions lacks the resources with which to account for the possibility of malfunctions. If functional types are defined in terms of historical success, then tokens that lack the defining property due to defect, and tokens that have lost the defining property due to disease or damage, are excluded from the functional category. Historically based malfunctions, in consequence, are impossible. The historical approach is no better than its non-historical competitors in accounting for the presumed normativity of functional properties.