In presenting this paper for the Festschrift in honor of my long time friend, Charles Hartshorne, I should state at once that I am writing as a biologist, specifically a geneticist, interested in the philosophical implications of his subject, but with only a superficial knowledge of philosophy in general. My justification for writing on this topic is the belief that the philosophy of science is necessarily a joint venture since it is obvious that advances in science provide data on the (...) nature of existence which must be taken into account in philosophical consideration of this subject. This is most obvious in connection with the drastic revision of the basic concepts of physics since 1900, the impact of which on philosophy has recently been brilliantly developed by Čapek. There have also been great advances in biology. The resulting concepts do not strike at the very categories of thought and defy expression in language as do those of modern physics. Nevertheless they have a special importance from the facts that the only direct knowledge of mind that any one possesses is associated with a certain living organism, himself, and that in general, indications of the presence of mind are restricted to living organisms. The fact that while such indications are universally accepted in the case of other human beings but become progressively less convincing as we pass to animals closely similar to man, and from these to such forms as fishes, insects, clams, worms and protozoa, raises difficulties. Few see any indication of mind in plants. (shrink)

The Nature of Selection is a straightforward, self-contained introduction to philosophical and biological problems in evolutionary theory. It presents a powerful analysis of the evolutionary concepts of natural selection, fitness, and adaptation and clarifies controversial issues concerning altruism, group selection, and the idea that organisms are survival machines built for the good of the genes that inhabit them. "Sober's is the answering philosophical voice, the voice of a first-rate philosopher and a knowledgeable student of contemporary evolutionary theory. His book merits (...) broad attention among both communities. It should also inspire others to continue the conversation."-Philip Kitcher, Nature "Elliott Sober has made extraordinarily important contributions to our understanding of biological problems in evolutionary biology and causality. The Nature of Selection is a major contribution to understanding epistemological problems in evolutionary theory. I predict that it will have a long lasting place in the literature."-Richard C. Lewontin. (shrink)

In The Structure of Biological Science I argued that the theory of natural selection is a statistical theory for reasons much like those which makes thermodynamics a statistical theory. In particular, the theory claims that fitness differences are large enough and the life span of species long enough for increases in average fitness always to appear in the long run; and this claim, I held, is of the same form as the statistical version of the second law of thermodynamics.For the (...) latter law also makes a claim about the long run, and its statistical character is due to this claim: thermodynamic systems must in the long run approach an equilibrium level of organization that maximizes entropy. Over finite times, given local boundary conditions, an isolated mechanical system, like the molecules in a container of gas, may sometimes interact so as to move the entropy of the system further from, instead of closer to the equilbrium level. But given enough interacting bodies, and enough time, the system will always eventually move in the direction prescribed by the law. Thus, we can attach much higher probabilities to the prediction that non-equilibrium systems will reflect greater entropy in future periods than we can to predictions that they will move in the opposite direction. And as we increase the amount of time and the number of bodies interacting, the strength of the probability we can attach to the prediction becomes greater and greater. (shrink)

Alexander Rosenberg (1994) claims that the omniscient viewpoint of the evolutionary process would have no need for the concept of random drift. However, his argument fails to take into account all of the processes which are considered to be instances of random drift. A consideration of these processes shows that random drift is not eliminable even given a position of omniscience. Furthermore, Rosenberg must take these processes into account in order to support his claims that evolution is deterministic and that (...) evolutionary biology is an instrumental science. (shrink)

This paper takes a critical look at the idea that evolutionary theory is a statistical theory. It argues that despite the strong instrumental motivation for statistical theories, they are not necessary to explain deterministic systems. Biological evolution is fundamentally a result of deterministic processes. Hence, a statistical theory is not necessary for describing the evolutionary forces of genetic drift and natural selection, nor is it needed for describing the fitness of organisms. There is a computational advantage to the statistical theory (...) of population genetics, but population genetics succeeds only by eliminating causes from its account of evolutionary change. (shrink)

We argue that Brandon and Carson's (1996) "The Indeterministic Character of Evolutionary Theory" fails to identify any indeterminism that would require evolutionary theory to be a statistical or probabilistic theory. Specifically, we argue that (1) their demonstration of a mechanism by which quantum indeterminism might "percolate up" to the biological level is irrelevant; (2) their argument that natural selection is indeterministic because it is inextricably connected with drift fails to join the issue with determinism; and (3) their view that experimental (...) methodology in botany assumes indeterminism is both false and incompatible with the commitment to discoverable causal mechanisms underlying biological processes. We remain convinced that the probabilism of the theory of evolution is epistemically, not ontologically, motivated. (shrink)

UNDERSTANDING SCIENTIFIC REASONING develops critical reasoning skills and guides students in the improvement of their scientific and technological literacy. The authors teach students how to understand and critically evaluate the scientific information they encounter in both textbooks and the popular media. With its focus on scientific pedagogy, UNDERSTANDING SCIENTIFIC REASONING helps students learn how to examine scientific reports with a reasonable degree of sophistication. The book also explains how to reason through case studies using the same informal logic skills employed (...) by scientists and to analyze a complex series of propositions and hypotheses using sound scientific reasoning. (shrink)

Do the sciences aim to uncover the structure of nature, or are they ultimately a practical means of controlling our environment? In Instrumental Biology, or the Disunity of Science, Alexander Rosenberg argues that while physics and chemistry can develop laws that reveal the structure of natural phenomena, biology is fated to be a practical, instrumental discipline. Because of the complexity produced by natural selection, and because of the limits on human cognition, scientists are prevented from uncovering the basic structure of (...) biological phenomena. Consequently, biology and all of the disciplines that rest upon it--psychology and the other human sciences--must aim at most to provide practical tools for coping with the natural world rather than a complete theoretical understanding of it. (shrink)

Evolutionary theory is thoroughly probabilistic, due to such elements as random mutation, random drift, and stochastic models of speciation and extinction. This uncontroversial claim raises a number of contentious issues: Is evolutionary theory probabilistic in any general sense, or only in a variety of particular, distinct senses? Are these processes inherently probabilistic, or does the use of probabilities simply provide a convenient way to camouflage a multitude of unknown causes? Does chance play an explanatory role in evolutionary theory, and if (...) so, how? My research explores the seemingly disparate meanings of biologists' various usages of the concept of chance in order to shed light on the answers to these questions. ;Recently, philosophers of science have looked to quantum mechanics to settle issues concerning the nature of chance. However, evolutionary theory itself has a decidedly probabilistic character, apart from quantum mechanics; evolutionary theory was given a probabilistic formulation prior to and independently of the development of quantum mechanics. Previous accounts of chance in evolutionary theory have focused primarily on one particular aspect of chance. I examine three distinct areas where chance enters into evolutionary theory in order to provide a comprehensive, synthetic account. Random drift has been the subject of much discussion by philosophers of biology, most notably by Beatty, Brandon, Hodge, Rosenberg, Shanahan, and Sober. My dissertation thus focuses on random drift in order to settle a number of unresolved controversies raised by these philosophers. The discussion of random drift provides a template for exploring random mutation and stochastic models of macroevolution. On the basis of these analyses, I argue that evolutionary theory provides reasons to rethink some of our traditional philosophical ideas about chance. (shrink)