Argument by analogy: The function of comparison in generalization and explanatory inferenc

It is a commonplace in the critical thinking literature that analogy is somehow tied to generalization. In Chapter One I briefly consider and criticize one version of this view---the "Entailment Account"---according to which analogical arguments exploit some (typically implicit) generalization. My primary concern is a more prevalent version---the "Heuristic Account"---according to which analogy contributes to the discovery of generalizations: analogies suggest, but do not justify. I contend that this account overlooks or undervalues the evidential function of analogy, particularly as analogy applies to explanatory inference.;In Chapter Two I examine the origin of the Heuristic Account in John Stuart Mill, whose position on analogy was enmeshed within his view of induction. I also consider contemporary counterparts to Mill.;I begin to question the adequacy of the Heuristic Account in Chapter Three, observing that Darwin clearly took his analogy between natural and artificial selection as evidentiary. I situate Darwin's analogy within his overall project, which follows an approach to scientific inquiry, elaborated by William Whewell and opposed by Mill, which stresses explanatory inference.;However, Whewell's account of explanatory inference is somewhat limited. Thus in Chapter Four I look at how the Whewellian tradition has evolved into more recent articulations. In Chapter Five I demonstrate how these contemporary insights provide us with a firmer grasp of just how Darwin's analogy played an evidentiary function in his theory, and thereby demonstrate the insufficiency of the Heuristic Account.;But in fact any attempt to understand analogy may require similar excavations into the complex intricacies of substantive examples---or even, as here, into a carefully targeted single case. Thus in Chapter Six I briefly speculate on possible further applications of the views I have considered.