The Nature of Scientific Explanation

Lecture Two. Induction: The Perennial Value of the Aristotelian Perspective

16 Lecture Two Induction the perennial value of the aristotelian perspective A well-thumbed Logic in use through most of the twentieth century is that of H. W. B. Joseph. First published in 1906 at 608 pages, it became the prototype of many a logic textbook written for classroom use. Joseph opens a chapter devoted to the problem of induction with the observation, “The history of the word Induction is still to be written, but it is certain that it has shifted its meaning in the course of time and that much misunderstanding has arisen thereby.”1 Volumes have been written in the last hundred years, but the conflict between the empiricist and the Aristotelian remains the same. Joseph shows clearly what Aristotle in the Posterior Analytics understood by induction. “Aristotle,” he tells us, “gives the name induction to the formal process of inference by which we conclude a proposition to hold universally of some class, or logical whole, because an enumeration shows it to hold for every part of that whole.”2 This may be called induction 1. H. W. B. Joseph, Logic (Oxford: Clarendon Press, 1906), 318. 2. Joseph, Logic, 318. 17 Lecture Two: Induction by complete enumeration, or perfect induction. Aristotle shows how it might be thrown into the form of an inductive syllogism. He points out that our knowledge of scientific principles springs historically out of our experience of particular facts, though its certainty rests ultimately on an act of intellectual insight. He gives the name “induction” to the process in which particulars of our experience suggest to us the principles that they exemplify, but this is not a formal process from premises to conclusion. It is not the enumeration that leads us to assent to the universal, but a kind of intellectual penetration. In Joseph’s account, Aristotle goes on to show “where (presumably in default of the necessary insight and assurance from our intellect) we may look for reasons for accepting or rejecting any principles that a science puts forward.”3 He does not give to this procedure, which is of a formal logical kind, the name of “induction ,” but calls it “dialectic.” What he says on this subject is of importance from the standpoint of scientific method and comes close to what modern writers understand by induction. There is no doubt that for Aristotle our knowledge of general principles comes from our experience of particular facts and that we arrive at those principles by induction. Yet the only formal logical process that Aristotle described under the name of induction is that of perfect induction, which clearly neither is nor can be the process by which the sciences establish their laws or general principles . The kinds of reasoning processes or arguments that they really do employ, so far as they appeal merely to the evidence of our experience, are of a different sort. The strength of Aristotle’s treatment of induction became an issue only in modernity, notably after Locke and Hume. Medieval Schoolmen and their contemporary exponents generally consider inductive reasoning unproblematic. The Schoolmen referred 3. Joseph, Logic, 391. An Aristotelian Perspective 18 to induction as an argument from experience. Albert the Great (1206–1280), for example, writes that our senses teach us the obvious truth about the nature of wine—that it intoxicates—and that our intellect grasps this truth with certainty that cannot be doubted. Modern logicians misunderstand this basic truth when they reduce it to no more than an invalid syllogism. Induction from an Aristotelian perspective, as Joseph shows, is not mere enumeration. Statistical models of induction miss the point when they reduce it to a mechanical process of enumerating cases. Such models fail to appreciate the cognitive leap, the intellectual discernment that produces the intelligible universal. One does not have to examine all instances of copper to understand that copper conducts electricity, conducts heat, and is malleable. The inductive insight is not mere enumeration, a statistical summary, or an endless enumeration. At some point the intellect recognizes that there is more in the sense report than the senses themselves are able to appreciate. Mere multiplication of instances serves no purpose. One of the best expositions and defenses of the perennial value of the Aristotelian perspective since Joseph is found in three works of Jacques Maritain, which may be read in tandem.4 Maritain dismisses perfect induction as the purely verbal and sterile form that modern commentators have...