Elliott Sober

I am grateful to Philip Kitcher for inviting me to comment on Alexander Rosenberg's (1996) review of Philosophy of Biology (Sober 1993) and to Rosenberg for his kind words about my book at the very beginning and the very end of his review. However, I cannot help feeling that most of the material in Rosenberg's review describes a different book from the one I wrote. Of the four philosophical claims that he ascribes to me, only one of them is asserted or implied in Philosophy of Biology. Rosenberg is right that I have argued that many evolutionary laws turn out, when stated carefully, to be a priori mathematical truths. However, he is mistaken in thinking that I am a "historicist" who holds that "fundamental theory in biology is narrative." Rosenberg also misconstrues my views on the meaning of probability statements in evolutionary theory.

Human nature is intriguing in such that it can express both negative and positive emotions, as in kindness and cruelty. The question is whether both are a natural part of our nature as human beings, or is one produced to serve as the alternate of the other. Another question that is brought to the table in this chapter is how does one determine what is natural and what is not, being its true definition? The chapter attempts to answer these questions based on evolution theory, whether events earlier in history served as a promoter for the emotions of today. Was the nature of kindness and caring inherent in a human being at the beginning of time, or is it only through the changes and events over time that it has developed? The chapter aims to aid the reader in understanding our human tendencies.

When philosophers defend epiphenomenalist doctrines, they often do so by way of a priori arguments. Here we suggest an empirical approach that is modeled on August Weismann’s experimental arguments against the inheritance of acquired characters. This conception of how epiphenomenalism ought to be developed helps clarify some mistakes in two recent epiphenomenalist positions – Jaegwon Kim’s (1993) arguments against mental causation, and the arguments developed by Walsh (2000), Walsh, Lewens, and Ariew (2002), and Matthen and Ariew (2002) that natural selection and drift are not causes of evolution. A manipulationist account of causation (Woodward 2003) leads naturally to an account of how macro- and micro-causation are related and to an understanding of how epiphenomenalism at different levels of organization should be understood.

How should the concept of evidence be understood? And how does the concept of evidence apply to the controversy about creationism as well as to work in evolutionary biology about natural selection and common ancestry? In this rich and wide-ranging book, Elliott Sober investigates general questions about probability and evidence and shows how the answers he develops to those questions apply to the specifics of evolutionary biology. Drawing on a set of fascinating examples, he analyzes whether claims about intelligent design are untestable; whether they are discredited by the fact that many adaptations are imperfect; how evidence bears on whether present species trace back to common ancestors; how hypotheses about natural selection can be tested, and many other issues. His book will interest all readers who want to understand philosophical questions about evidence and evolution, as they arise both in Darwin's work and in contemporary biological research.

John Beatty (1995) and Alexander Rosenberg (1994) have argued against the claim that there are laws in biology. Beatty's main reason is that evolution is a process full of contingency, but he also takes the existence of relative significance controversies in biology and the popularity of pluralistic approaches to a variety of evolutionary questions to be evidence for biology's lawlessness. Rosenberg's main argument appeals to the idea that biological properties supervene on large numbers of physical properties, but he also develops case studies of biological controversies to defend his thesis that biology is best understood as an instrumental discipline. The present paper assesses their arguments.

It is widely held that in the eighteenth and nineteenth and centuries history came into its own as a proper object of scientific scrutiny, and that the work of Darwin and Marx was decisive in this regard. We readily concede the revolutionary character of Darwinism and Marxism in relation to earlier accounts of natural and human history. And we agree too, as is widely supposed, that there are important conceptual affinities joining Darwin's theory of evolution and Marx's theory of history. However, it has not been sufficiently appreciated how these theories differ-precisely in the sense they count as historical. Evolutionary theory and historical materialism exemplify different strategies for making history an object of theoretical investigation. By reflecting on these differences, we can gain some purchase on the kind of theory historical materialism is and appreciate the very special sense in which Marx did indeed construct an historical theory.

Presented in an engaging lecture-style format, this anthology leads readers through a series of discussions on the basic issues and ideas in philosophy, with lectures supported by related readings from historically important sources. The discussions emphasize the logic of philosophical arguments—and in particular, how they relate to the content of scientific theories such as evolution. This five-part book, made up of “lectures” and readings, covers an introduction to philosophy; the philosophy of religion; theory of knowledge; philosophy of mind; and ethics. For anyone looking for adequate answers to enduring questions.

How could the fundamental mental operations which facilitate scientific theorizing be the product of natural selection, since it appears that such theoretical methods were neither used nor useful "in the cave"-i.e., in the sequence of environments in which selection took place? And if these wired-in information processing techniques were not selected for, how can we view rationality as an adaptation? It will be the purpose of this paper to address such questions as these, and in the process to sketch some of the considerations that an evolutionary account of rationality may involve. By describing the broad framework within which the evolution of rationality may eventually be understood, I hope to undermine the idea that evolutionary theory is somehow incapable of dealing with this characteristic and requires supplementation by some novel principle. A more modest ambition of the paper is to try to provoke those who think that there are special problems involved in this evolutionary inquiry to say what these problems are.

Alexander Rosenberg begins his recent article on the concept of fitness with the remark that "debates about the cognitive status of the Darwinian theory of natural selection should have ended long ago." I agree that this obsession needs to be overcome. But Rosenberg repeats some of the old mis- takes and invents epicycles on others. In this comment I will not be able to circumscribe fully the range of topics that an adequate treatment of this cluster of problems demands. A few critical re marks will indicate what I find wanting in Rosenberg's treatment

I want to explore what happens to two philosophical issues when we assume that the mind, a functional device, is to be understood by the same sort of functional analysis that guides biological investigation of other organismic systems and characteristics. The first problem area concerns the concept of rationality, its connection with reliability and reproductive success, and the status of rationality hypotheses in attribution of beliefs. It has been argued that ascribing beliefs to someone requires the assumption that that person is rational. It also has been argued that evolutionary theory can account for the capacity we have for rational thought by appealing to the idea that rational methods for constructing beliefs are reliable and therefore represented a selected advantage. Both of these claims about rationality are critically examined. In the second part of the paper, I turn to some criticisms that have been advanced against "functionalist" solutions to the mind/body problem. These criticisms are defused when that doctrine is understood in terms of a Teleological (rather than a Turing Machine) notion of function. However, functionalism does not emerge totally unscathed. Voltaire's Dr. Pangloss saw everything in terms of its function and its perfect performance of its function. In the philosophy of mind, his influence lives on in the form of two ideas: (i) that we must possess rational methods for constructing beliefs, since our minds are the product of natural selection, and (ii) that psychological states and properties are individuated by their psychological functions. Contemporary biology provides the resources for avoiding Pangloss's wideeyed teleology in the study of adaptation. It is to be hoped that progress in psychology will loosen the grip of Panglossian assumptions in the study of mind.

Realism and empiricism have always been contradictory tendencies in the philosophy of science. The view I will sketch is a synthesis, which I call Contrastive Empiricism. Realism and empiricism are incompatible, so a synthesis that merely conjoined them would be a contradiction. Rather, I propose to isolate important elements in each and show that they combine harmoniously. I will leave behind what I regard as confusions and excesses. The result, I hope, will be neither contradiction nor mishmash.

Quine has developed two reasons for thinking that our ontology should not include the ontological category of properties. His first point is that the criterion for individuating properties is unclear, and the second is that postulating the existence of properties would not explain anything. In what follows I critically examine these two themes, which I will call the clarity argument and the parsimony argument. Although I will suggest that these two arguments are defective, I also will try to show that certain related arguments on behalf of the existence of properties are likewise flawed. This will set the stage for the discussion in the fourth section of the perspective provided by evolutionary theory on the question of the ontological status of properties. It will emerge that evolutionary theory provides reason for thinking that properties exist, and, additionally, gives an interesting point of view on the epistemological and metaphysical issues that Quine has addressed.

A phylogeny that allows for lateral gene transfer (LGT) can be thought of as a strictly branching tree (all of whose branches are vertical) to which lateral branches have been added. Given that the goal of phylogenetics is to depict evolutionary history, we should look for the best supported phylogenetic network and not restrict ourselves to considering trees. However, the obvious extensions of popular tree-based methods such as maximum parsimony and maximum likelihood face a serious problem—if we judge networks by fit to data alone, networks that have lateral branches will always fit the data at least as well as any network that restricts itself to vertical branches. This is analogous to the well-studied problem of overfitting data in the curve-fitting problem. Analogous problems often have analogous solutions and we propose to treat network inference as a case of model selection and use the Akaike Information Criterion (AIC). Strictly tree-like networks are more parsimonious than those that postulate lateral as well as vertical branches. This leads to the conclusion that we should not always infer LGT events whenever it would improve our fit-to-data, but should do so only when the improved fit is larger than the penalty for adding extra lateral branches.

The reception so far of Kitcher's Vaulting Ambition reminds me of the old saw about the difference between an optimist and a pessimist. Looking at the same glass of water, the former sees it as half full while the latter sees it as half empty. Some have seen Kitcher's book as a vindication of the possibility of an evolutionary science of human behavior; others have seen it as a devastating critique of the most influential efforts to date to construct such a science. As in the joke about the water glass, both assessments have their point. Sociobiology is a research program, not a unified theory. What one can do is test particular hypotheses within this program and see whether they live up to reasonable standards of rigor and evidence. This is what Kitcher does, with great energy and care.

Adaptationism is a doctrine that has meant different things to different people. In this essay, I want to isolate and discuss a reading of adaptationism that makes it a non-trivial empirical thesis about the history of life. I'll take adaptationism to be the following claim: natural selection has been the only important cause of most of the phenotypic traits found in most species. I won't try to determine whether adaptationism, so defined, is true. Rather, my task will be one of clarification. What does this statement mean, and how is it related to various remarks that biologists have made about adaptationism, pro and con?

The examples and concepts that Shoemaker cites are rather heterogeneous. Some distinctions need to be drawn. An optimality thesis involves not just an ordering of options, but a value judgment about them. So let us begin by distinguishing minimality from optimality. And the concept of minimality can play a variety of roles, among which I distinguish between extremum descriptions, statements hypothesizing an optimizing process, and methodological recommendations. Finally, I consider how the three categories relate to Shoemaker’s question that “Who is optimizing: the scientist or nature?”

Egoism and altruism need not be characterized as single factor theories of motivation, according to which there is a single kind of preference that moves people to action. Rather, each asserts a claim of causal primacy—a claim as to which sort of preference is the more powerful influence on behavior. This paper shows that this idea of causal primacy can be clarified in a standard scientific way. This formulation explains why many observed behaviors fail to discriminate between the hypothesis that the agent is altruistic and the hypothesis that the agent is egoistic. A distinction between altruistic motivation and altruistic action is then drawn, from which it follows that it is an open question how often altruists behave altruistically

I discuss two versions of the doomsday argument. According to ``Gott's Line'',the fact that the human race has existed for 200,000 years licences the predictionthat it will last between 5100 and 7.8 million more years. According to ``Leslie'sWedge'', the fact that I currently exist is evidence that increases the plausibilityof the hypothesis that the human race will come to an end sooner rather than later.Both arguments rest on substantive assumptions about the sampling process thatunderlies our observations. These sampling assumptions have testable consequences,and so the sampling assumptions themselves must be regarded as empirical claims.The result of testing some of these consequences is that both doomsday argumentsare empirically disconfirmed.

Instrumentalism is usually understood as a semantic thesis: scientific theories are neither true nor false, but are merely instruments for making predictions. Scientific realists are on firm ground when they reject this semantic claim. This paper focuses on epistemological rather than semantic instrumentalism. This form of instrumentalism claims that theories are to be judged by their ability to make accurate predictions, and that predictive accuracy is the only consideration that matters in the end. I consider how instrumentalism is related to a quite different proposal concerning how theories should be evaluated—scientific realism. Instrumentalism allows for the fact that a false model can get one closer to the truth than a true one.

We argue elsewhere that explanatoriness is evidentially irrelevant . Let H be some hypothesis, O some observation, and E the proposition that H would explain O if H and O were true. Then O screens-off E from H: Pr = Pr. This thesis, hereafter “SOT” , is defended by appeal to a representative case. The case concerns smoking and lung cancer. McCain and Poston grant that SOT holds in cases, like our case concerning smoking and lung cancer, that involve frequency data. However, McCain and Poston contend that there is a wider sense of evidential relevance—wider than the sense at play in SOT—on which explanatoriness is evidentially relevant even in cases involving frequency data. This is their main point, but they also contend that SOT does not hold in certain cases not involving frequency data. We reply to each of these points and conclude with some general remarks on screening-off as a test of evidential relevance