Abstract

Research programmes are sets of problems preferred on epistemic grounds and including preferred heuristics for inquiry. Charles Lyell's research programme for biogeograpy includes the problem of explaining the distribution of species constrained by laws governing locomotion and containment of species. Included in the programme are laws governing the supernatural introduction of replacement species. Wallace and Darwin derected arguments against the putative intelligibility of this aspect of Lyell's programme before discovering natural selection, and their defence, at this time of natural laws governing the introduction of new species is interesting as a defence of a noval programme of research, not a defence of a proposed theroy. These arguments are presented and an epistemological foundation is offered for them. 1 The author is indebted to a referee for helpful comments on an earlier draft of this paper.