Abstract

One of the most intriguing mysteries in American philosophy falls under the question: “Just what does Charles Sanders Peirce’s concept of abductive reasoning comprise?” Peirce used the terms “abduction” and “retroduction” interchangeably as names for a distinct form of logical inference, as well as for the method by which hypotheses are engendered. He considered his theory of abduction essential to his theory of pragmatism. Yet nearly a century after his death, Peirce’s concept of abduction is still poorly understood. This entry will explore the two distinct meanings of the intertwined concepts that Peirce variously called “abduction” and “retroduction.” One meaning refers to a distinct form of logical inference; the other, to the form of a deliberate and overarching logical method which incorporates abduction, deduction, and induction for its full performance. If modern researchers were to accept this proposed separation of Peirce¹s terminology to identify these different levels of concepts within his notion of abduction, we could finally begin the task of developing effective operational definitions for abduction and retroduction. These definitions would take us a long way toward solving the “mystery” about what Peirce meant by his concept of abduction and toward making “right reasoning” a teachable skill.