Does natural selection act primarily on individual organisms, on groups, on genes, or on whole species? The question of levels of selection - on which biologists and philosophers have long disagreed - is central to evolutionary theory and to the philosophy of biology. Samir Okasha's comprehensive analysis gives a clear account of the philosophical issues at stake in the current debate.

Samir Okasha offers a critical study of agential thinking in biology, where evolved organisms are seen as agents pursuing a goal. He examines the justification for transposing concepts from rational humans to the biological world, and considers whether agential thinking is mere anthropomorphism or plays a more intellectual role in the science.

What is science? Is there a real difference between science and myth? Is science objective? Can science explain everything? This Very Short Introduction provides a concise overview of the main themes of contemporary philosophy of science. Beginning with a short history of science to set the scene, Samir Okasha goes on to investigate the nature of scientific reasoning, scientific explanation, revolutions in science, and theories such as realism and anti-realism. He also looks at philosophical issues in particular sciences, (...) including the problem of classification in biology, and the nature of space and time in physics. The final chapter touches on the conflicts between science and religion, and explores whether science is ultimately a good thing. (shrink)

We consider the question: under what circumstances can the concept of adaptation be applied to groups, rather than individuals? Gardner and Grafen (2009, J. Evol. Biol.22: 659–671) develop a novel approach to this question, building on Grafen's ‘formal Darwinism’ project, which defines adaptation in terms of links between evolutionary dynamics and optimization. They conclude that only clonal groups, and to a lesser extent groups in which reproductive competition is repressed, can be considered as adaptive units. We re-examine the conditions under (...) which the selection–optimization links hold at the group level. We focus on an important distinction between two ways of understanding the links, which have different implications regarding group adaptationism. We show how the formal Darwinism approach can be reconciled with G.C. Williams’ famous analysis of group adaptation, and we consider the relationships between group adaptation, the Price equation approach to multi-level selection, and the alternative approach based on contextual analysis. (shrink)

Covering some of science's most divisive topics, such as philosophical issues in genetics and evolution, the philosophy of biology also encompasses more traditional philosophical questions, such as free will, essentialism, and nature vs nurture. Here, Samir Okasha outlines the core issues with which contemporary philosophy of biology is engaged.

Biologists and philosophers of biology typically regard essentialism about speciesas incompatible with modern Darwinian theory. Analytic metaphysicians such asKripke, Putnam and Wiggins, on the other hand, believe that their essentialist thesesare applicable to biological kinds. I explore this tension. I show that standard anti-essentialist considerations only show that species do not have intrinsic essential properties. I argue that while Putnam and Kripke do make assumptions that contradict received biological opinion, their model of natural kinds, suitably modified, is partially applicable to (...) biological species. However, Wiggins'' thesis that organisms belong essentially to their species is untenable, given modern species concepts. I suggest that Putnam''s, Kripke''s and Wiggins'' errors stem from adopting an account of the point of scientific classification which implies that relationally-defined kinds are likely to be of little value, an account which is inapplicable to biology. (shrink)

This volume explores from multiple perspectives the subtle and interesting relationship between the theory of rational choice and Darwinian evolution. In rational choice theory, agents are assumed to make choices that maximize their utility; in evolution, natural selection 'chooses' between phenotypes according to the criterion of fitness maximization. So there is a parallel between utility in rational choice theory and fitness in Darwinian theory. This conceptual link between fitness and utility is mirrored by the interesting parallels between formal models of (...) evolution and rational choice. The essays in this volume, by leading philosophers, economists, biologists and psychologists, explore the connection between evolution and rational choice in a number of different contexts, including choice under uncertainty, strategic decision making and pro-social behaviour. They will be of interest to students and researchers in philosophy of science, evolutionary biology, economics and psychology. (shrink)

Sceptical arguments in epistemology typically employ sceptical hypotheses, which are rivals to our everyday beliefs so constructed that they fit exactly the evidence on which those beliefs are based. There are two ways of using a sceptical hypothesis to undermine an everyday belief, giving rise to two distinct sorts of sceptical argument: underdetermination‐based and closure‐based. However, both sorts of argument, as usually formulated in the literature, fall foul of evidential holism, for they ignore the crucial role of background beliefs. An (...) analogy with the philosophy of science makes this point explicit. There is no simple way to “holism proof” the two sceptical arguments. (shrink)

Discoverer of the theory of evolution by natural selection, and thus the founder of modern evolutionary biology, Charles Darwin is responsible for one of the most fundamental and far‐reaching contributions to the modern scientific world view. Born in 1809 in Shrewsbury into a wealthy Victorian family, Darwin was educated at the universities of Edinburgh and Cambridge. Though his formal education was of little interest to him ‐ “my time was wasted, as far as the academical studies were concerned” (1969, p. (...) 58) ‐ Cambridge did provide the opportunity to pursue his childhood interest in natural history. Upon graduating in 1831, Darwin joined a charting expedition around South America on board HMS Beagle, which was to last for five years. During this time, he made lengthy expeditions inland, studying the flora, fauna, and geology of South America and the Pacific Islands, and accumulating a massive biological and geological collection. These years were critical for Darwin's intellectual development, as he admitted, sowing the seeds of his doubt in the fixity of individual species. Darwin was impressed by a large number of facts that could not be explained on the assumption of the fixity of species, including the close structural similarities between extinct and living species revealed by the fossil record. Most important of all were the tortoises and finches of the Galapagos Islands: each island was inhabited by very similar, yet distinct varieties ‐ clear evidence for Darwin of common ancestry shaped by adaptation to local conditions. The creatures of the Galapagos, Darwin wrote, bring us close “to that great fact ‐ that mystery of mysteries ‐ the first appearance of new beings on this earth” (1839, p. 466). (shrink)

For a number of years, the debate in evolutionary biology over the ’levels of selection’ has attracted intense interest from philosophers of science. The main question concerns the level of the biological hierarchy at which natural selection occurs. Does selection act on organisms, genes, groups, colonies, demes, species, or some combination of these? According to traditional Darwinian theory the answer is the organism -- it is the differential survival and reproduction of individual organisms that drives the evolutionary process. But there (...) are alternative views too, including pluralist views which say that the choice between different levels of selection is often a matter of perspective, not empirical fact. (shrink)

A number of recent philosophers, including Michael Williams, Barry Stroud and Donald Davidson, have argued that scepticism about the external world stems from the foundationalist assumption that sensory experience supplies the data for our beliefs about the world. In order to assess this thesis, I offer abrief characterisation of the logical form of sceptical arguments. I suggest that sceptical arguments rely on the idea that many of our beliefs about the world are ‘underdetermined’ by the evidence on which they are (...) based. Drawing on this characterisation of scepticism, I argue that Williams, Stroud andDavidson are right to see the foundationalist assumption as essential to the sceptic’s argument, but wrong to think that scepticism is inevitable once that assumption is in place. By pursuing an analogy with some recent debates in the philosophy of science, I try to locate the additional assumptions which the sceptic must make, in order to derive her conclusion. (shrink)

The idea that natural selection can operate on cultural as well as genetic variation is central to recent theories of cultural evolution. This raises an overarching question: how much of traditional evolutionary theory, which was formulated in population-genetic terms, can survive intact once the possibility of cultural inheritance is taken into account? This question is addressed in relation to R. A. Fisher’s “fundamental theorem” of natural selection. Though Fisher’s theorem may appear to be an essentially genetic result, a version of (...) the theorem can be derived that applies to any evolving population, with an arbitrary inheritance mechanism. However, I argue that the biological significance of this “generalized” version of the fundamental theorem is less than that of the Fisherian original. (shrink)

This symposium contains a selection of the papers that were presented at a conference we organized on Rational Choice and Philosophy that was held at Vanderbilt University on 16 and 17 May 2014. The aim of the conference was to provide an inter-disciplinary forum for philosophical work that uses ideas and tools from rational choice theory, understood broadly to include decision theory, game theory and social choice theory.

A long-established consensus in the philosophy of biology holds that biological species are not natural kinds with intrinsic essences, despite what Putnam (1975) and Kripke (1980) thought. This anti-essentialist consensus has recently been challenged by Michael Devitt, who insists that it rests on a mistake. According to Devitt, philosophers of biology have failed to recognise the distinction between two quite different questions one can ask about species: the Category question and the Taxon question. The various “species concepts” found in the (...) biological literature are attempts to answer the former but are silent about the latter, Devitt claims, so do not conflict with essentialism, pace what philosophers of biology believe. By carefully attending to the logical relation between the Category and Taxon questions, Devitt’s claim that the anti-essentialist consensus rests on a mistake is shown to be untenable. (shrink)

This is a collection of high-quality research papers in the philosophy of science, deriving from papers presented at the second meeting of the European Philosophy of Science Association in Amsterdam, October 2009.

Biological agency has received much attention in recent philosophy of biology. But what is the motivation for introducing talk of agency into biology and what is meant by “agent”? Two distinct motivations can be discerned. The first is that thinking of organisms as agents helps to articulate what is distinctive about organisms vis-à-vis other biological entities. The second is that treating organisms as agent-like is a useful heuristic for understanding their evolved behavior. The concept of agent itself may be understood (...) in at least four different ways: minimal agent, intelligent agent, rational agent, and intentional agent. Which understanding is most appropriate depends on which of the two motivations we are concerned with. (shrink)

Kuhn’s famous thesis that there is ‘no unique algorithm’ for choosing between rival scientific theories is analysed using the machinery of social choice theory. It is shown that the problem of theory choice as posed by Kuhn is formally identical to a standard social choice problem. This suggests that analogues of well-known results from the social choice literature, such as Arrow’s impossibility theorem, may apply to theory choice. If an analogue of Arrow’s theorem does hold for theory choice this would (...) refute Kuhn’s thesis, but it would also pose a threat to the rationality of science, a threat that is if anything more worrying than that posed by Kuhn. Various possible ‘escape routes’ from Arrow’s impossibility result are examined, in particular Amartya Sen’s idea of ‘enriching the informational basis’. It is shown that Sen’s idea can be applied to the problem of theory choice in science. This in turn sheds light on two well-known approaches to inductive inference in philosophy of science: Bayesianism and statistical model selection. (shrink)

Abstract:This paper explores the contrast between mentalistic and behaviouristic interpretations of decision theory. The former regards credences and utilities as psychologically real, while the latter regards them as mere representations of an agent's preferences. Philosophers typically adopt the former interpretation, economists the latter. It is argued that the mentalistic interpretation is preferable if our aim is to use decision theory for descriptive purposes, but if our aim is normative then the behaviouristic interpretation cannot be dispensed with.

Hamilton’s theory of kin selection is the best-known framework for understanding the evolution of social behavior but has long been a source of controversy in evolutionary biology. A recent critique of the theory by Nowak, Tarnita, and Wilson sparked a new round of debate, which shows no signs of abating. In this overview, we highlight a number of conceptual issues that lie at the heart of the current debate. We begin by emphasizing that there are various alternative formulations of Hamilton’s (...) rule, including a general version, which is always true; an proximate version, which assumes weak selection; and a special version, which demands other restrictive assumptions. We then examine the relationship between the neighbor-modulated fitness and inclusive fitness approaches to kin selection. Finally, we consider the often-strained relationship between the theories of kin and multilevel selection. (shrink)

I examine the argument that scientific theories are typically 'underdetermined' by the data, an argument which has often been used to combat scientific realism. I deal with two objections to the underdetermination argument: (i) that the argument conflicts with the holistic nature of confirmation, and (ii) that the argument rests on an untenable theory/data dualism. I discuss possible responses to both objections, and argue that in both cases the proponent of underdetermination can respond in ways which are individually plausible, but (...) that the best response to the first objection conflicts with the best response to the second. Consequently underdetermination poses less of a problem for scientific realism than has often been thought. (shrink)

Kin selection and multilevel selection are alternative approaches for studying the evolution of social behaviour, the relation between which has long been a source of controversy. Many recent theorists regard the two approaches as ultimately equivalent, on the grounds that gene frequency change can be correctly expressed using either. However, this shows only that the two are formally equivalent, not that they offer equally good causal representations of the evolutionary process. This article articulates the notion of an ‘adequate causal representation’ (...) using causal graphs, and then seeks to identify circumstances under which kin and multilevel selection do and do not satisfy the test of causal adequacy. 1 Introduction2 The KS and MLS Approaches2.1 The MLS decomposition2.2 The KS decomposition3 Equivalence and Causality4 Two Problem Cases4.1 The non-social trait case4.2 Genotypic selection with meiotic drive5 Casual Adequacy: A Graphical Approach5.1 The basic idea5.2 Graphs with individual and group variables5.3 Cases where KS is causally adequate5.4 Cases where MLS is causally adequate6 Discussion6.1 Relation to previous work. (shrink)

Christie, Brusse, et al. claim that the ‘selected effect’ (SE) theory of function is premised on a simplistic view of evolution. In complex evolutionary scenarios, in particular those involving frequency-dependent selection (FDS), the SE theory fails, they argue, since citing a trait’s SE function does not serve to explain why the trait exists. I argue that where FDS leads to a stable equilibrium, at which all individuals’ trait values constitute a ‘best response’ to the rest of the population, the SE (...) theory can be straightforwardly applied. However, matters are different if the evolutionary dynamics do not take the population to a stable equilibrium. (shrink)

Cancer is often seen as a case of multilevel selection, in which selfish cancer cells pursue short-term proliferation to the detriment of the collective. Thus cancer cells are described as ‘cheats’, and an analogy is often drawn between the mechanisms by which organisms fight cancer and the mechanisms by which social groups enforce cooperation. Recently, Andy Gardner and Max Shpak and Jie Lu have argued that cancer is not a true case of multilevel selection, that cancer cells should be not (...) regarded as cheats, and that the analogy between anti-cancer adaptations and suppression mechanisms in social groups is misleading. Their arguments are powerful. However, by drawing on the (presumed) link between cancer and the evolution of multicellularity, the notion that cancer represents a form of selective conflict between cells and organisms can be salvaged. (shrink)

A number of recent biologists have used multi-level selection theory to help explain the major transitions in evolution. I argue that in doing so, they have shifted from a ‘synchronic’ to a ‘diachronic’ formulation of the levels of selection question. The implications of this shift in perspective are explored, in relation to an ambiguity in the meaning of multi-level selection. Though the ambiguity is well-known, it has never before been discussed in the context of the major transitions.

Many philosophers agree that Hume was not simply objecting to inductive inferences on the grounds of their logical invalidity and that his description of our inductive behaviour was inadequate, but none the less regard his argument against induction as irrefutable. I argue that this constellation of opinions contains a serious tension. In the light of the tension, I re-examine Hume’s actual sceptical argument and show that the argument as it stands is valid but unsound. I argue that it can only (...) be converted into a sound one if our inductive behaviour can be characterized as a process of rule-governed ampliation. Drawing on some Bayesian ideas, I argue that our inductive behaviour probably cannot be characterized in that way, so our immunity from Hume is secure. Finally, I compare my response to Hume’s argument with some other well known responses. (shrink)

This paper provides a philosophical analysis of the ongoing controversy surrounding R.A. Fisher's famous ‘fundamental theorem’ of natural selection. The difference between the ‘traditional’ and ‘modern’ interpretations of the theorem is explained. I argue that proponents of the modern interpretation have captured Fisher's intended meaning correctly and shown that the theorem is mathematically correct, pace the traditional consensus. However, whether the theorem has any real biological significance remains an unresolved issue. I argue that the answer depends on whether we accept (...) Fisher's non-standard notion of environmental change, on which the theorem rests; arguments for and against this notion are explored. I suggest that there is a close link between Fisher's fundamental theorem and the modern ‘gene's eye’ view of evolution. Introduction What Does the Fundamental Theorem Say? Key Concepts Explained Alleged Significance of the FTNS Traditional versus Modern Interpretations of the FTNS The Modern Interpretation Illustrated Fisher's Concept of ‘Environmental Change’ Causality and the Modern Interpretation The Significance of the FTNS Re-considered Appendix CiteULike Connotea Del.icio.us What's this? (shrink)

In this paper, I explore Larry Laudan's and Jarrett Leplin's recent claim that empirically equivalent theories may be differentially confirmed. I show that their attempt to prise apart empirical equivalence and epistemic parity commits them to two principles of confirmation that Hempel demonstrated to be incompatible.

The group selection controversy is about whether natural selection ever operates at the level of groups, rather than at the level of individual organisms. Traditionally, group selection has been invoked to explain the existence of altruistic behaviour in nature. However, most contemporary evolutionary biologists are highly sceptical of the hypothesis of group selection, which they regard as biologically implausible and not needed to explain the evolution of altruism anyway. But in their recent book, Elliot Sober and David Sloan Wilson [1998] (...) argue that the widespread opposition to group selection is founded on conceptual confusion. The theories that have been propounded as alternatives to group selection are actually group selection in disguise, they maintain. I examine their arguments for this claim, and John Maynard Smith's arguments against it. I argue that Sober and Wilson arrive at a correct position by faulty reasoning. In the final section, I examine the issue of how to apply the principle of natural selection at different levels of the biological hierarchy, which underlies the dispute between Sober and Wilson and Maynard Smith. (shrink)

In a recent article I compared the problem of theory choice, in which scientists must choose between competing theories, with the problem of social choice, in which society must choose between competing social alternatives. I argued that the formal machinery of social choice theory can be used to shed light on the problem of theory choice in science, an argument that has been criticized by Michael Morreau and Jacob Stegenga. This article replies to Morreau’s and Stegenga’s criticisms.

Two alternative statistical approaches to modelling multi-level selection in nature, both found in the contemporary biological literature, are contrasted. The simple covariance approach partitions the total selection differential on a phenotypic character into within-group and between-group components, and identifies the change due to group selection with the latter. The contextual approach partitions the total selection differential into different components, using multivariate regression analysis. The two approaches have different implications for the question of what constitutes group selection and what does not. (...) I argue that the contextual approach is theoretically preferable. This has important implications for a number of issues in the philosophical debate about the levels of selection. Introduction Group selection and the covariance formulation of selection The contextual approach A modification of the simple covariance approach Consequences: frameshifting and additivity 5.1 Frameshifting 5.2 Additivity Conclusion. (shrink)

John Harsanyi and John Rawls both used the veil of ignorance thought experiment to study the problem of choosing between alternative social arrangements. With his ‘impartial observer theorem’, Harsanyi tried to show that the veil of ignorance argument leads inevitably to utilitarianism, an argument criticized by Sen, Weymark and others. A quite different use of the veil-of-ignorance concept is found in evolutionary biology. In the cell-division process called meiosis, in which sexually reproducing organisms produce gametes, the chromosome number is halved; (...) when meiosis is fair, each gene has only a fifty percent chance of making it into any gamete. This creates a Mendelian veil of ignorance, which has the effect of aligning the interests of all the genes in an organism. This paper shows how Harsanyi's version of the veil-of-ignorance argument can shed light on Mendelian genetics. There turns out to be an intriguing biological analogue of the impartial observer theorem that is immune from the Sen/Weymark objections to Harsanyi's original. View HTML Send article to KindleTo send this article to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle. Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply. Find out more about the Kindle Personal Document Service.SOCIAL JUSTICE, GENOMIC JUSTICE AND THE VEIL OF IGNORANCE: HARSANYI MEETS MENDELVolume 28, Issue 1Samir Okasha DOI: https://doi.org/10.1017/S0266267112000119Your Kindle email address Please provide your Kindle [email protected]@kindle.com Available formats PDF Please select a format to send. By using this service, you agree that you will only keep articles for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services. Please confirm that you accept the terms of use. Cancel Send ×Send article to Dropbox To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about sending content to Dropbox. SOCIAL JUSTICE, GENOMIC JUSTICE AND THE VEIL OF IGNORANCE: HARSANYI MEETS MENDELVolume 28, Issue 1Samir Okasha DOI: https://doi.org/10.1017/S0266267112000119Available formats PDF Please select a format to send. By using this service, you agree that you will only keep articles for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services. Please confirm that you accept the terms of use. Cancel Send ×Send article to Google Drive To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about sending content to Google Drive. SOCIAL JUSTICE, GENOMIC JUSTICE AND THE VEIL OF IGNORANCE: HARSANYI MEETS MENDELVolume 28, Issue 1Samir Okasha DOI: https://doi.org/10.1017/S0266267112000119Available formats PDF Please select a format to send. By using this service, you agree that you will only keep articles for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services. Please confirm that you accept the terms of use. Cancel Send ×Export citation Request permission. (shrink)

In models of multi-level selection, the property of Darwinian fitness is attributed to entities at more than one level of the biological hierarchy, e.g. individuals and groups. However, the relation between individual and group fitness is a controversial matter. Theorists disagree about whether group fitness should always, or ever, be defined as total (or average) individual fitness. This paper tries to shed light on the issue by drawing on work in social choice theory, and pursuing an analogy between fitness and (...) utility. Social choice theorists have long been interested in the relation between individual and social utility, and have identified conditions under which social utility equals total (or average) individual utility. These ideas are used to shed light on the biological problem. (shrink)