Philosophers of science have developed an account of causal-mechanical explanation that captures regularity, but this account neglects variation. In this article I amend the philosophy of mechanisms to capture variation. The task is to explicate the relationship between regular causal mechanisms responsible for individual development and causes of variation responsible for variation in populations. As it turns out, disputes over this relationship have rested at the heart of the nature–nurture debate. Thus, an explication of the relationship between regular causal mechanisms (...) and causes of variation and between individual development and variation offers both the necessary amendment to the philosophy of mechanisms and the resources to mediate the dispute. (shrink)

Philosophers of science widely believe that the hereditarian theory about racial differences in IQ is based on methodological mistakes and confusions involving the concept of heritability. I argue that this "received view" is wrong: methodological criticisms popular among philosophers are seriously misconceived, and the discussion in philosophy of science about these matters is largely disconnected from the real, empirically complex issues debated in science.

Genetic differences can lead to phenotypic differences either directly or indirectly (via causing differences in external environments, which then affect phenotype). This possibility of genetic effects being mediated by environmental influences is often used by scientists and philosophers to argue that heritability is not a very helpful causal or explanatory notion. In this paper it is shown that these criticisms are based on serious misconceptions about methods of behavior genetics.

It is worthy to supplement Charney with two historical issues: (1) There were two rival trends in the rebirth of genetic thought in the 1960s: the universal and the variation related. This traditional duality suggested that heredity cannot be equated with genetic determinism. (2) The classical debates and reinterpretation of adoption/twin studies in the 1980s regarding intelligence suggested that the environment had a more active role in unfolding the genetic program.

Discussions about the biological bases (or lack thereof) of the concept of race in the human species seem to be never ending. One of the latest rounds is represented by a paper by Neven Sesardic, which attempts to build a strong scientific case for the existence of human races, based on genetic, morphometric and behavioral characteristics, as well as on a thorough critique of opposing positions. In this paper I show that Sesardic’s critique falls far short of the goal, and (...) that his positive case is exceedingly thin. I do this through a combination of analysis of the actual scientific findings invoked by Sesardic and of some philo- sophical unpacking of his conceptual analysis, drawing on a dual professional background as an evolu- tionary biologist and a philosopher of science. (shrink)

The method in human genetics of ascribing causal responsibility to genotype by the use of heritability estimates has been heavily criticized over the years. It has been argued that these estimates are rarely valid and do not serve the purpose of tracing genetic causes. Recent contributions strike back at this criticism. I present and discuss two opposing views on these matters represented by Richard Lewontin and Neven Sesardic, and I suggest that some of the disagreement is based on differing concepts (...) of genetic causation. I use the distinction of structuring and triggering causes to help clarifying the basis for the opposing views. (shrink)

Recognizing that all traits are the result of an interaction between genes and environment, I offer a set of criteria for nevertheless making sense of our practice of singling out certain traits as genetic ones, in effect making a distinction between causes and mere conditions. The central criterion is that a trait is genetic if it is genetic differences that make the differences in that trait variable in a given population. A second criterion requires that genetic traits be individuated in (...) a way that matches what some genetic factors cause specifically. Clarifying our causal and classificatory language here can help us to avoid confusions of both theoretical and practical significance. (shrink)

Recent challenges to non-traditional theories of natural kinds demand clarifications and revisions to those theories. Highlights: The semantics of natural kind terms is a special case of a general naturalistic conception of signaling in organisms that explains the epistemic reliability of signaling. Natural kinds and reference are two aspects of the same natural phenomenon. Natural kind definitions are phenomena in nature not linguistic or representational entities; their relation to conceptualized definitions is complex. Reference and truth are special cases of a (...) broader phenomenon of accommodation between aspects of signaling and epistemically relevant causal structures. (shrink)

Philosophers of mind (from eliminative materialists to psychofunctionalists to interpretivists) generally assume that a normative ideal delimits which mental phenomena exist (though they disagree about how to characterize the ideal in question). This assumption is dubious. A comprehensive ontology of mind includes some mental phenomena that are neither (a) explanatorily fecund posits in any branch of cognitive science that aims to unveil the mechanistic structure of cognitive systems nor (b) ideal (nor even progressively closer to ideal) posits in any given (...) folk psychological practice. Indeed, one major function of scientific psychology has been (and will be) to introduce just such (normatively suboptimal but real) mental phenomena into folk psychological taxonomies. The development and public dissemination of IQ research over the course of the 20th Century is a case in point. (shrink)