Peter Smith

Maynard Smith is right that one of the most striking features of contemporary biology is the ever-increasing prominence of the concept of information, along with related concepts like representation, programming, and coding. Maynard Smith is also right that this is surely a phenomenon which philosophers of science should examine closely. We should try to understand exactly what sorts of theoretical commitment are made when biological systems are described in these terms, and what connection there is between semantic descriptions in biology and in other domains.

A wide range of ecological and evolutionary models predict variety in phenotype or behavior when a population is at equilibrium. This heterogeneity can be realized in different ways. For example, it can be realized through a complex population of individuals exhibiting different simple behaviors, or through a simple population of individuals exhibiting complex, varying behaviors. In some theoretical frameworks these different realizations are treated as equivalent, but natural selection distinguishes between these two alternatives in subtle ways. By investigating an increasingly complex series of models, from a simple fluctuating selection model up to a finite population hawk/dove game, we explore the selective pressures which discriminate between pure strategists, mixed at the population level, and individual mixed strategists. Our analysis reveals some important limitations to the ESS framework often employed to investigate the evolution of complex behavior.

Where to begin? I’ll take three books from my shelves. First, now nearly forty years old, a little book of television lectures by the great physicist Richard Feynman, The Character of Physical Law. He talks about the laws of motion, the inverse square law of gravitation, conservation laws, symmetry principles and the various ways these all hang together. Feynman obviously takes it that it is a prime aim of science to discover such laws. But what are laws? He writes – and this is about his one and only shot at a characterization at the level of abstraction that we might think of as philosophical –.

Metaphysics is once again a thriving subdiscipline within philosophy, despite a long tradition of challenges to the very viability of the metaphysical enterprise. The criticisms have not so much been satisfactorily answered, as shouldered aside by the vigorous development of the field. Some focused meta-theoretic discussion has recently arisen within mainstream metaphysics.1 The present paper is written more from an outsider's vantage point. I attempt to give a new meta-theory for some parts of metaphysics. The central claim is that much metaphysical work, especially of the contemporary systematic kind, might best be understood as model-building, in a specific sense of this term that draws on recent philosophy of science.

“Triviality arguments” against functionalism in the philosophy of mind hold that the claim that some complex physical system exhibits a given functional organization is either trivial or has much less content than is usually supposed. I survey several earlier arguments of this kind, and present a new one that overcomes some limitations in the earlier arguments. Resisting triviality arguments is possible, but requires functionalists to revise popular views about the “autonomy” of functional description.

Drawing on models of communication due to Lewis and Skyrms, I contrast sender-receiver systems as they appear within and between organisms, and as they function in the bridging of space and time. Within the organism, memory can be seen as the sending of messages over time, communication between stages as opposed to spatial parts. Psychological memory and genetic memory are compared with respect to their relations to a sender-receiver model. Some puzzles about “genetic information” can be resolved by seeing the genome as a cell-level memory with no sender

A “sender–receiver” framework based on models developed in several fields can provide a general treatment of communicative and symbolic phenomena, replacing traditional semiotic theories that have failed to live up to the hopes of their advocates. Sender–receiver models have mostly been applied to linguistic behavior, gestures, and other ephemeral interactions between individuals. I look at the application of this framework to enduring artifacts, including pictures, using indigenous rock art in Australia as a case study.

Research in archaeology and anthropology on the evolution of modern patterns of human behavior often makes use of general theories of signs, usually derived from semiotics. Recent work generalizing David Lewis’ 1969 model of signaling provides a better theory of signs than those currently in use. This approach is based on the coevolution of behaviors of sign production and sign interpretation. I discuss these models and then look at applications to human prehistoric behavior, focusing on body ornamentation, tools, and other artifacts.

The paper links discussions of two topics: biological individuality and the simplest forms of mentality. I discuss several attempts to locate the boundary between metabolic activity and ‘minimal cognition.’ I then look at differences between the kinds of individuality present in unicellular life, multicellular life in general, and animals of several kinds. Nervous systems, which are clearly relevant to cognition and subjectivity, also play an important role in the form of individuality seen in animals. The last part of the paper links these biological transitions to the evolutionary history of subjective experience.

One way to express the most persistent part of the mind-body problem is to say that there is an “explanatory gap” between the physical and the mental. The gap is not usually taken to apply to all of the mental, but to subjective experience, the mind’s “qualitative” features, or what is now referred to as “phenomenal consciousness.” The “gap” formulation is due to Joseph Levine. He acknowledged the appeal of intuitions of separability between physical facts, of any kind we can envisage, and this aspect of our mental lives. Subjective experience seems not to be the sort of thing that is just the physical under another guise. The immediate focus of Levine’s discussion was a family of arguments due to Saul Kripke. Kripke argued that some influential claims of mind-body identity could not be, as materialists claimed, contingent. If these identities are real then they are necessary. But we can clearly conceive that the mental and physical could come apart—an intuition that “identity theorists” conceded. Given that the identity is necessarily present if present at all, from the fact it is not necessary we can see it is absent. Kripke concluded that physicalism is false. Levine wanted to resist this

It is well known that informational theories of representation have trouble accounting for error. Informational semantics is a family of theories attempting a naturalistic, unashamedly reductive explanation of the semantic and intentional properties of thought and language. Most simply, the informational approach explains truth-conditional content in terms of causal, nomic, or simply regular correlation between a representation and a state of affairs. The central work is Dretske, and the theory was largely developed at the University of Wisconsin by Fred Dretske, Dennis Stampe, and Berent Enc. Recently, informational semantics has roamed far beyond its Wisconsin home, and built a sizeable collection of followers. Converts include Jerry Fodor, Robert Stalnaker and, less faithfully, Paul and Patricia Churchland and Hartry Field. But for some years informational semantics has been hounded by a problem with error – the classic presentation is Fodor – and no other problem has hounded the theory so persistently.