Ludwik Fleck's reasonable relativism about science

An ongoing project in the philosophy of science and medicine is the effort to articulate a form of relativism about science that can find a path between strongly realist and pernicious relativist poles. Recent scholarship on relativism has described the characteristics a philosophy must have in order to be considered a thoroughgoing relativism. These include non-absolutism, multiplicity, dependence, incompatibility, equal validity and non-neutrality. Critics of relativism maintain that these requirements cannot be met without collapsing into a pernicious form of relativism and that attempts to do so have failed. Against this view, I argue that the early twentieth century philosophy of Ludwik Fleck satisfies these requirements. Paying attention to the scientific details of Fleck's account of active and passive elements of knowledge, and the resistance generated by them, reveals a thoroughgoing and yet reasonable relativism about science.