Biology, philosophy of

4. The varieties of biology

Most work to date in philosophy of biology has concerned evolution (see Evolution, theory of), but the subject is by no means solely restricted to evolutionary biology. Increasingly philosophers are also engaging with issues in ecology, in developmental biology, in molecular biology and in newer areas such as systems biology (see Ecology; Genetics; Molecular biology). In these areas, once again, there is an interplay between technical issues that are largely specific to biology, and issues that will be familiar to general philosophers of science. Consider the example of reduction. Often discussions about reduction concern the thought that explanatory concepts, or entities, at one theoretical level can be dispensed with, and replaced by explanatory concepts, or entities, at some lower level (see Reduction, problems of). So, for example, one might claim that mental properties can be reduced to neural properties (see Reductionism in the philosophy of mind). In biology it has sometimes been claimed that advances in molecular biology, including discoveries regarding the structure of DNA and role of chromosomes in inheritance, indicate the reducibility of Mendelian genetics to molecular genetics. While technical issues regarding the precise details of molecular biology are relevant here, so are more general issues about reduction in the sciences.

The disproportionate attention that philosophers of biology have given to evolution can be explained in part by the role that evolutionary theory has had in knitting together many other branches of biology (see Modern synthesis, the), in part by the extraordinarily broad explanatory power that natural selection appears to have (see Natural selection and adaptation) and in part by the impact our kinship with other plant and animal species is held to have on philosophical conceptions of human nature (see Human nature). The explanatory reach of evolutionary theory has made it the object of considerable social and political concern. Ever since Darwin’s time, for example, the relationship between evolution and religious belief has been vigorously debated (see Evolution and religion). It is hardly surprising, then, that philosophers have been so drawn to examining in detail the nature of evolution, and the explanatory scope and limits of natural selection. But we should perhaps expect the balance of philosophical attention to even up somewhat, as molecular biology, ecology and other newer branches of the life-sciences begin to attract similar levels of social and political concern.