Darwin's Long and Short Arguments

Abstract

Doren Recker has criticized the prevailing accounts of Darwin's argument for the theory of natural selection in the Origin of Species. In this note I argue that Recker fails to distinguish between a deductive short argument for the principle of natural selection, and a non-deductive, long argument which aims at establishing that the principle has explanatory power in the various domains of application. I shall try to show that the semantic view of theories, especially in its structuralist form, makes it easy to distinguish between the two arguments and to explain how Darwin's long argument counts as one argument. I also raise a question about Recker's views on Darwin's mid-Victorian background, arguing that Newton's First Rule of Reasoning was not just a constraint on hypotheses involving unobservables, but a general request to keep conjecture and certainty apart.