This chapter discusses the controversy between Mill and Whewell over the confirmation of scientific theories. This debate is related to their differing opinions over the nature of inductive inference and the type of knowledge we can reach inductively. Whewell believed we could make reliable probable inferences to empirical truths about unobserved causes and entities. Mill, on the other hand, denied us even probable knowledge of unobserved causes and entities. Thus Whewell accepted, and Mill rejected, the claim that through science, we can gain knowledge of the underlying causal structure of nature. This difference is reflected in their respective views about classification. Whewell maintained that scientists discover groupings of things that reflect the causal structure of the physical world; that is, scientists discover natural kinds.
Keywords: causal structure, scientific theories, nature, entities, physical world, causes