Peter R Smith

The concept of information has acquired a strikingly prominent role in contemporary biology. This trend is especially marked within genetics, but it has also become important in other areas, such as evolutionary theory and developmental biology, particularly where these fields border on genetics. The most distinctive biological role for informational concepts, and the one that has generated the most discussion, is in the description of the relations between genes and the various structures and processes that genes play a role in causing. For many biologists, the causal role of genes should be understood in terms of their carrying information about their various products. That information might require the cooperation of various environmental factors before it can be "expressed," but the same can be said of other kinds of message. An initial response might be to think that this mode of description is entirely anchored in a set of well-established facts about the role of DNA and RNA within protein synthesis, summarized in the familiar chart representing the "genetic code," mapping DNA base triplets to amino acids. However, informational enthusiasm in biology predates even a rudimentary understanding of these mechanisms (Schrodinger 1944). And more importantly, current applications of informational concepts extend far beyond anything that can receive an obvious justification in terms of the familiar facts about the specification of protein molecules by DNA. This includes: 1 (i) The description of whole-organism phenotypic traits (including complex behavioral traits) as specified or coded for by information contained in the genes, (ii) The treatment of many causal processes within cells, and perhaps of the wholeorganism developmental sequence, in terms of the execution of a program stored in the genes, (iii) The idea that genes themselves, for the purpose of evolutionary theorizing, should be seen as, in some sense, "made" of information..

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.

We present a dynamic model of the evolution of communication in a Lewis signaling game while systematically varying the degree of common interest between sender and receiver. We show that the level of common interest between sender and receiver is strongly predictive of the amount of information transferred between them. We also discuss a set of rare but interesting cases in which common interest is almost entirely absent, yet substantial information transfer persists in a *cheap talk* regime, and offer a diagnosis of how this may arise.

A number of recent discussions have argued that George Price's equationfor representing evolutionary change is a powerful and illuminatingtool, especially in the context of debates about multiple levels ofselection. Our paper dissects Price's equation in detail, and comparesit to another statistical tool: the calculation and comparison ofaverage fitnesses. The relations between Price's equation and equationsfor evolutionary change using average fitness are closer than issometimes supposed. The two approaches achieve a similar kind ofstatistical summary of one generation of change, and they achieve thisvia a similar loss of information about the underlying fitnessstructure.

In the Wednesday Logic Reading Group, where we are working through Sara Negri and Jan von Plato’s Structural Proof Theory – henceforth ‘NvP’ – I today introduced Chapter 6, ‘Structural Proof Analysis of Axiomatic Theories’. In their commendable efforts to be brief, the authors are sometimes a bit brisk about motivation. So I thought it was worth trying to stand back a bit from the details of this action-packed chapter as far as I understood it in the few hours I had to prepare, and to try to give an overall sense of the project. These are the notes I wrote for myself. As often with such middle-of-term efforts dashed off in a couple of hours, I both would have liked to do better and do more justice to what we are reading, but I also just don’t have time to do more now than make a few corrections to the first version. So the usual warning applies: caveat lector.

Modeling work by Brian Skyrms and others in recent years has transformed the theoretical role of David Lewis's 1969 model of signaling. The latter can now be understood as a minimal model of communication in all its forms. In this article, we explain how the Lewis model has been generalized, and consider how it and its variants contribute to ongoing debates in several areas. Specifically, we consider connections between the models and four topics: The role of common interest in communication, signaling within the organism, meaning, and the evolution of human communication and language.

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

Why do octopuses matter to philosophy? They matter to the part of philosophy concerned with the mind. To see why, we step back and think about the evolutionary connections between all living things. Biologists think of these relationships in terms of a tree of life. This is a huge tree-like pattern, marking which species are close relatives and which are distantly connected. The vertebrates form one branch of the tree, and that is where we find nearly all the animals with large and complex brains. These include ourselves, other mammals, and birds. In evolutionary terms, these are all cousins. In the huge area of the tree containing other animals, invertebrates, there is only one small branch where we also find large brains. This branch contains the cephalopods – octopuses, cuttlefish, and squid. Large nervous systems evolved separately on these two branches, and nowhere else. Octopuses are a separate experiment in the evolution of the mind. Meeting an octopus is like meeting an intelligent alien. So what did this experiment produce? Here is one thing. The nervous system of an octopus is less centralized than ours. In fact, more than half of the octopus' neurons are not in the animal's central "brain" at all, but in the eight arms. It is as if each arm has a mind of its own. Or perhaps in an octopus we see intelligence without a unified self

How does science work? Does it tell us what the world is "really" like? What makes it different from other ways of understanding the universe? In Theory and Reality, Peter Godfrey-Smith addresses these questions by taking the reader on a grand tour of more than a hundred years of debate about science. The result is a completely accessible introduction to the main themes of the philosophy of science. Examples and asides engage the beginning student; a glossary of terms explains key concepts; and suggestions for further reading are included at the end of each chapter. Like no other text in this field, Theory and Reality combines a survey of recent history of the philosophy of science with current key debates that any beginning scholar or critical reader can follow. The second edition is thoroughly updated and expanded by the author with a new chapter on truth, simplicity, and models in science.

Lockdowns and related policies of behavioral and economic restriction introduced in response to the COVID-19 pandemic are criticized, drawing on three sets of ideas and arguments that are organized in accordance with the likely degree of controversy associated with their guiding assumptions. The first set of arguments makes use of cost–benefit reasoning within a broadly utilitarian framework, emphasizing uncertainty, the role of worst-case scenarios, and the need to consider at least the medium term as well as immediate effects. The second draws on assumptions about the political value of basic liberties. The third draws on ideas about the roles of different stages within human life.