Biological Reductionism

Abstract

The problems of biological reductionism, that is, questions of the relationship between whole organisms and their parts, fall into three domains: ontological, methodological, and epistemological. Ontological reductionism occurs when an organism is found to be exhaustively composed of the same components as inorganic matter. Methodological reductionism is the claim that the best strategy of research is to study living phenomena at the lowest levels of complexity. Epistemological reductionism results if the laws and theories of biology can be derived as special cases of the laws and theories of the physical sciences.

The mechanism versus vitalism issue belongs to the ontological domain, as does the issue of emergent properties. All evidence indicates that organisms are exhaustively composed of nonliving atoms and that life processes can be explained without recourse to any substantive nonmaterial entity. However, atoms in association do display properties not normally included among those of isolated atoms, and in practice there is no way to ascertain what properties one object may show in conjunction with any other.

Methodological reductionism seems justified in a moderate form: often the best strategy of research is an alternation between analysis and synthesis. This moderate position finds support from epistemological reductionists, who admit the heuristic value of nonreductionistic experiments, and from opponents of epistemological reductionism, who nevertheless think that organisms should be studied at all levels of integration.

Epistemological reduction of one theory to another takes the form of a deductive argument in which one of the premises is the primary theory and the conclusion is the secondary theory. This operation requires that the disparate terms of the two theories be connected by suitable definitions. These conditions have been largely satisfied in the reduction of thermodynamics to statistical mechanics, the reduction of chemical valence theory to the physics of orbital electrons, and the reduction of some of genetics to molecular biology. If the reduction of one science to another is not possible at present, then claims that such a reduction will be possible in the future carry little weight. In any case, there is an unresolved residue accompanying any attempt at epistemological reductionism, and the terms and patterns of explanation in some sciences seem wholly unconnectable with those of other sciences. For these reasons it seems unlikely that complete epistemological reduction of biology to physics will ever be possible. Nevertheless, epistemological reduction of biology to physics will ever be possible. Nevertheless, epistemological reductions are successful forms of scientific explanation and remain a reasonable goal of scientific work. —The Editor