Middle Positions
John Hedley Brooke, 21 July 1983
The Darwin scholar, John Greene, once summarised the Darwinian revolution as the triumph of a dynamic and non-teleological structuring of nature over static, teological systems: the triumph of chance and change over design and permanence, the triumph of objectivity in the life sciences, of secularism and naturalism over clericalism and the supernatural. The form of such a characterisation is familiar enough – perhaps too familiar in the sense that we are apt to take for granted the structuring of historical material through dichotomies and antitheses. Such has been the stuff of scientific as well as historical exposition. When Galileo launched his controversial defence of Copernican cosmology, he insisted on a dialogue between two chief world systems. When Darwin published his Origin of Species, he fortified his argument by contrasting the strengths of his own theory with the inadequacies of ‘separate creation’. Within the subsequent history of evolutionary mechanics other dichotomies have become part of the folklore of science: ‘In effect, only two theories of evolution have ever been put forward,’ writes John Maynard Smith, ‘one, originating with Lamarck … the other originating with Darwin.’ Such reduction of the scientific corpus to patterns of mutual exclusivity doubtless tells us something about the strategy, if not the logic, of scientific corroboration. It is a form of reductionism which popular works on the historiography of science have done little to discourage. Thomas Kuhn’s The Structure of Scientific Revolutions envisaged competition between two rival and incommensurable ‘paradigms’ as the hallmark of a revolutionary period. A greater theoretical diversity and the science had to be regarded as immature and consigned to a pre-paradigm era. The discontinuity theses of Michel Foucault have lent themselves to a similar dualistic rigidity. Witness the use made of his ‘epistemes’ by N.C. Gillespie, who, in his recent study of Charles Darwin and the Problem of Creation (1979), implied that there were only two epistemes worth talking about: the ‘positivist’, with its exclusion of metaphysics and natural theology, and the ‘creationist’, which was ultimately, if not immediately, grounded in the supernatural.–