Inductive Generalizations and Manipulative Abduction

A better understanding of manipulative abduction at the level of scientific experiment could improve our knowledge of induction and its distinction from abduction: manipulative abduction can be considered as a kind of basis for further meaningful inductive generalizations. For example different generated “construals” can give rise to different inductive generalizations. It is difficult to grasp this distinction through present logical models of the induction/abduction puzzle. 1 Manipulative Abduction I have introduced the concept of manipulative abduction contrasted with theoretical abduction [Magnani, 2001] to illustrate situations where we are thinking through doing and not only, in a pragmatic sense, about doing. So the idea of manipulative abduction goes beyond the well-known role of experiments as capable of forming new scientific laws by means of the results (nature’s answers to the investigator’s question) they present, or of merely playing a predictive role (in confirmation and in falsification). Manipulative abduction refers to an extra-theoretical behavior that aims at creating communicable accounts of new experiences to integrate them into previously existing systems of experimental and linguistic (theoretical) practices. The existence of this kind of extra-theoretical cognitive behavior is also testified by the many everyday situations in which humans are perfectly able to perform very efficacious (and habitual) tasks without the immediate possibility of realizing their conceptual explanation. In some cases the conceptual account for doing these things was at one point present in the memory, but now has deteriorated, and it is necessary to reproduce it, in other cases the account has to be constructed for the first time, like in creative settings of manipulative abduction in science. Hutchins (1995) illustrates the case of a navigation instructor that for 3 years performed an automatized task involving a complicated set of plotting manipulations and procedures. The insight concerning the conceptual relationships between relative and geographic motion came to him suddenly “as lay in his bunk one night”. This example explains that many forms of learning can be represented as the result of the capability of giving conceptual and theoretical details to already automatized manipulative executions. The instructor does not discover anything new from the point of view of the objective knowledge about the involved skill, however, we can say that his conceptual awareness is new from the local perspective of his individuality. In this kind of action-based abduction the suggested hypotheses are inherently ambiguous until articulated into configurations of real or imagined entities (images, models or concrete apparatus and instruments). In these cases only by experimenting we can discriminate between possibilities: they are articulated behaviorally and concretely by manipulations and then, increasingly, by words and pictures. Gooding [Gooding, 1990] refers to this kind of concrete manipulative reasoning when he illustrates the role in science of the so-called “construals” that embody tacit inferences in procedures that are often apparatus and machine based. They belong to the pre-verbal context of ostensive operations, that are practical, situational, and often made with help of words, visualizations, or concrete artifacts. The embodiment is of course an expert manipulation of objects in a highly constrained experimental environment, and is directed by abductive movements that imply the strategic application of old and new templates of behavior mainly connected with extra-theoretical components, for instance emotional, esthetical, ethical, and economic. The hypothetical character of construals is clear: they can be developed to examine further chances, or discarded; they are provisional creative organization of experience and some of them become in their turn hypothetical interpretations of experience, that is more theory-oriented, their reference is gradually stabilized in terms of established observational practices. Step by step the new interpretation – that at the beginning is completely “practice-laden” – relates to more “theoretical” modes of understanding (narrative, visual, diagrammatic, symbolic, conceptual, simulative), closer to the constructive effects of theoretical abduction. When the reference is stabilized the effects of incommensurability with other established observations can become evident. But it is just the construal of certain phenomena that can be shared by the sustainers of rival theories. [Gooding, 1990] shows how Davy and Faraday could see the same attractive and repulsive actions at work in the phenomena they respectively produced; their discourse and practice as to the role of their construals of phenomena clearly demonstrate they did not inhabit different, incommensurable worlds in some cases. Moreover, the experience is constructed, reconstructed, and distributed across a social network of negotiations among the different scientists by means of construals. These construals aim at arriving to a shared understanding overcoming all conceptual conflicts. As I said above they constitute a provisional creative organization of experience: when they become in their turn hypothetical interpretations of experience, that is more theory-oriented, their reference is gradually stabilized in terms of established and shared observational practices that also exhibit a cumulative character. It is in this way that scientists are able to communicate the new and unexpected information acquired by experiment and action. 2 Samples, Induction, and Abduction I think that a better understanding of manipulative abduction at the level of scientific experiment could improve our knowledge of induction, and its distinction from abduction: manipulative abduction can be considered as a kind of basis for further meaningful inductive generalizations. For example different generated construals can give rise to different inductive generalizations. It is difficult to grasp this distinction through present logical models of the induction/abduction puzzle. Josephson [Josephson, 2000] maintains that “An inductive generalization is an inference that goes from the characteristics of some observed sample of individuals to a conclusion about the distribution of those characteristics in some larger populations” (p. 40). Then he stresses the attention to the fact that what characterizes the sample as “representative” is its effect (sample frequency) by reference to part of its cause (population frequency): this should be considered a conclusion about its cause. In this sense abduction plays an important role If we do not think of inductive generalizations as abductions, we are at a loss to explain why such inference is made stronger or more warranted, if in connecting data we make a systematic search for counter-instances and cannot find any, than it would be we just take the observation passively. Why is the generalization made stronger by making an effort to examine a wide variety of types of A’s? The answer is that it is made stronger because the failure of the active search of counter-instances tend to rule out various hypotheses about ways in which the sample might be biased, that is, it strengthens the abductive conclusion by ruling out alternative explanations for the observed frequency (p. 42).