Informal Reasoning and Education

James F. Voss, David N. Perkins, Judith W. Segal, James F. Voss, David N. Perkins, Judith W. Segal

• Publisher: Routledge
• Year: 2012
• ISBN:
  9781136463525
• Edition: 1
• Topic: Education
• Subtopic: Education General

Based on extensive reasoning acquisition research, this volume provides theoretical and empirical considerations of the reasoning that occurs during the course of everyday personal and professional activities. Of particular interest is the text's focus on the question of how such reasoning takes place during school activities and how students acquire reasoning skills.

I CONTEXTS FOR INFORMAL REASONING

1 Informal Reasoning in Science

Ryan D. Tweney
Bowling Green State University

That informal reasoning plays a large role in scientific inquiry is a point that is relatively undisputed among scholars and scientists studying science itself. At least since Kuhn's Scientific Revolutions (1962/1970), inquiry into the nature of science has acknowledged that science does not rely exclusively, or even primarily, on formal modes of reasoning. Although the results of science are frequently expressed in the formal language of mathematics and with heavy reliance on inferential logic, few current scholars expect results to originate in formal ways. Recently, there has been a great tendency to ascribe certain very irrational processes to science: Kekulé’s dream, for example, or the lucky accidents of Fleming. On this view, science can begin to seem a very arbitrary process indeed (see, e.g., Austin's 1978 book, Chase, Chance, and Creativity: The Lucky Art of Novelty, the subtitle of which leaves no doubt about its message!)

In fact, however, the point can be stretched too far. Although we may all agree that luck, dreams, and wild associations play a role in science, this is not the same as ascribing such irrationality to all scientific thought. Although it is not formal, the informal reasoning that occurs in science is rational, in the sense that it is goal-directed, sometimes highly systematic, and fully justifiable on pragmatic grounds. Baron (1985) has even argued that we can create normative schemes of informal reasoning. Perkins (1981) has argued that many of the processes underlying creative thought correspond to rather ordinary processes of thought applied in novel contexts. I hope to show in this chapter that the further analysis of informal reasoning in science has potentially great explanatory power for an understanding of scientific thought.

In another context (Tweney, 1989), I have argued that understanding complex, real-world thought requires moving beyond the rather narrow laboratory research that has characterized much of cognitive psychology and must include, also, an effort to apply the generalizations of cognitive psychology to the interpretive understanding of complex thought in vivo. Such an approach requires closer attention to case studies of scientific thinking than is customary in recent psychology (see also Wallace & Gruber, 1989). Although there is now a greater willingness to deal with idiographic materials in cognitive work, most of the descriptive base is still depersonalized. We do not, in general, know much of the life of the subjects in the ordinary study of, say, problem solving. There may be an incredibly detailed analysis of an hour's worth of cognition, but rarely are ties made between the results of the analysis and anything else that may or may not be knowable about the “subject”—whose very identity still hides behind that jargonized term.

As an alternative approach, I offer a case study based on the thinking of the English physicist Michael Faraday (1791–1867). Because he kept extensive diaries and notes, we have, perhaps, more raw material for such an analysis than for any other scientist. If a plausible account of Faraday's thought is possible, and if it reveals in more detail how informal reasoning processes are manifest in science, then the effort should exemplify one of the main themes of this volume of essays and support my claim about the importance of case study analysis. Cognition of the sort we are describing occurs in persons, and we neglect the uniqueness of the cognizer at our peril (see Gruber, 1974, for a similar claim).

FARADAY'S SCIENTIFIC ACHIEVEMENTS

Faraday is important in the history of science primarily for his empirical and theoretical investigations into the nature of electricity and magnetism. He is sometimes regarded as the first true field theorist in the line of thinking that leads to relativity and quantum theory (Einstein & Infeld, 1938). A brilliant experimentalist, Faraday published the results of thousands of experiments and kept records of literally tens of thousands conducted during his career. As a theorist, he was the first to present a cogent field theory as a genuine alternative to 18th century interpretations of Newtonian theory. Whereas the Newtonian universe consisted of hard material objects (“billiard balls” on an atomic scale), acting upon each other at a distance, via forces whose nature was not explained, Faraday's universe was filled with forces only and dispensed to a large degree with matter as a primary physical reality. For Faraday, the Newtonian “billiard ball” atoms were instead conceived of as centers of force. The mystery of action-at-a-distance was replaced by imponderable but real lines of force that reach out from the centers to fill all space (Williams, 1966). In Faraday's account, matter is a stage on which the primary reality, namely forces, acts.

Ultimately, Faraday was able to ground his conception of lines of force on a number of empirical phenomena: the patterned arrangement of iron filings in a magnetic field, the conversion of electric currents into magnetic forces and vice versa, the quantitative relationships governing the forces on a magnetic needle placed near a current-carrying wire, and so on. Faraday never developed his theory in formal mathematical terms (a task carried out by others, most notably, James Clerk Maxwell [1831–1874]), nor did he succeed in grounding all aspects of his theory empirically. Thus, for example, he never succeeded in verifying his strong belief that gravity was somehow related to electrical and magnetic phenomena; as a result, his system never fully exorcised action-at-a-distance from physics. Nevertheless, Faraday's theory was so rich in empirical consequences and so compelling as an alternate world view, that he fully deserves the revolutionary status sometimes accorded him.

In his research, Faraday consciously moved from vague construals to formal concepts and precise quantitative laws, pursuing experimental demonstrations of striking simplicity (rather than mathematical formalisms) to convince the scientific community of the Tightness of his views (Gooding, 1985). Showing some of the ways in which he did this is the major focus of this chapter.

FARADAY THE PERSON

Before we can know how he reasoned, we must know a few things about Faraday. He has been the subject of a number of excellent biographical studies, most notably those of Tyndall (1868), Thompson (1898), Williams (1965), and, most recently, the studies in the collection edited by Gooding and James (1985). Several crucial aspects of Faraday's cognitive style are revealed in these studies: his reliance on visual imagery, the presuppositions that he brought to science, the social effects of the research of his contemporaries (and the way he utilized their results), and so on.

Especially striking for our purpose is the heavy reliance that Faraday placed on manipulation as a source of knowledge. Experimentation was his royal road to truth and the final test of all of his ideas. Although he held very strong beliefs about the nature of the physical world, he was always careful to distinguish between what he believed to be true and what he could demonstrate to be true via experiment; if something were true, then it should lead to ways of acting on the world in tangible and fruitful fashion. Faraday's epistemology was procedural in a very basic sense (Tweney, 1987b; see also Gooding, 1985, and Gooding, 1990). His epistemology coincided neatly with his force-centered ontology. Just as forces were, for him, the primary physical reality (a “push–pull” universe), so also was manipulation the primary means of getting knowledge (a “push–pull” view of truth).

Both his epistemology and his ontology have early origins in Faraday's intellectual development. Born poor, he received only a little formal schooling before being apprenticed to a bookbinder. While learning his trade, Faraday read some of the books that he bound, most notably an Encyclopedia Britannica article on electricity (Tytler, 1797) and a popular work, Jane Marcet's Conversations on Chemistry (1809). He later identified Marcet's book as an early source for his reliance on experimentation; when he tried her experiments, they actually worked as she said they would! As he later wrote, “I felt that I had got hold of an anchor in chemical knowledge and clung fast to it” (Letter to De La Rive, October 2, 1858, in Williams, 1971, p. 912).

Faraday's self-education in science, itself a fascinating tale, is not detailed here. Suffice it to say that, by 1813, when he was plucked from the binding trade to serve as bottle washer, amaneuensis, and gofer for the eminent scientist Sir Humphry Davy (1778–1829), Faraday had already acquired a basic knowledge of science. Bright and hard-working, his role in Davy's lab expanded quickly. His first scientific paper was published only 3 years later (Faraday, 1816a), and, only 5 years after, he caused a sensation in the scientific community by discovering that a current-carrying wire could be made to revolve in a magnetic field (Faraday, 1821).

The force-centered view that characterizes Faraday's physical theory can be seen in embryonic form in some of his earliest notebooks. In an 1816 commonplace book, he copied out the following quote from Laplace: “The true march of Philosophy consists in rising by the path of Induction and calculation from phenomena to laws and from laws to forces” (Faraday, 1816b, p. 335). Although we can discount the “Induction and calculation” part of the quote (fairly standard boilerplate for the times), it is significant that Faraday approvingly noted the explanatory role of forces in physical science. In the same notebook, Faraday speculated on the meaning of action-at-a-distance formulations and queried whether or not electrostatic induction could be seen as an example of action-at-a-distance. Beginning in the same year, he gave a series of lectures on chemistry (Faraday, 1816–1818). Force concepts also played a major role in these lectures, although, at the beginning, he stuck to a basically Newtonian view of matter.

In another context, I have traced the development of his force schema after 1816 (Tweney, 1985). The important point here is that this schema evolved slowly and continuously across the years, but without altering the fundamental point: that forces are central and that matter is secondary, something to be explained by forces rather than as an ultimate reality in itself. It is not surprising, therefore, that an interest in magnetic and electrical phenomena is present in his very earliest notes (Faraday, 1809–1810). Finally, we must acknowledge the central influence of Davy on Faraday's conceptualizations. Heavily influenced by Coleridge, Davy was a neo-Kantian and himself an advocate of the importance of electrical forces in the composition of matter. In fact, Davy was the first to see the significance of the phenomena of electrolytic decomposition (Davy, 1812; Forgan, 1980).

It is also important to note the religious roots of Faraday's views (Cantor, 1985). A devout Sandemanian, Faraday was a fundamentalist who believed that God had made it possible to “read the book of nature” but that doing so required enormous effort with no guarantee that the right answers would be attained. God would not deceive, but neither was God's nature an open book! Further, the human desire for knowledge was sometimes hindered by human weakness, by pride, conceit, and sloth. Out of this view, Faraday drew a kind of humility that was of great usefulness to his scientific work. Alert to the possibility of self-deception, he was consciously aware of the danger of confirmation bias and of the need to avoid it by deliberate attempts to disconfirm. Such views supported his reliance on experiment as the test of truth. Moreover, as Cantor (1985) has noted, Faraday's distrust of mathematical formulations in science (there are no mathematical equations of any sort in any of his papers) stem also from religious grounds. Sandemanians relied on numbers as signs of God's will, using, for example, simple lotteries to determine church seating. But they eschewed any transformations of these numbers—one could not weight the lots, for example—because this amounted to a distortion of God's message. In the same way, Faraday relied heavily on quantification but never used abstract formalisms to distort the message of the quantified relationships. Instead of algebra, he relied on a kind of intuitive geometry, a visual depiction of physical reality manifested in careful diagrams and verbal descriptions for the mind's eye (Maxwell, 1855; Gooding & Tweney, in preparation).

In sum, then, we can see that Faraday's approach to science was structured by his characteristics as a person. The product of a specific cultural, social, and historical context, his unique background and education in science further shaped the way he thought. Although unsurprising in itself, this point serves to introduce the more specific question of exactly how he carried out his research and what kinds of informal reasoning were manifest within it.

FARADAY'S EXPERIMENTAL SCIENCE:
A SPECIFIC EXAMPLE

To illustrate the role of informal reasoning in Faraday's experimental work, I focus on one episode, a series of experiments carried out from August to November of 1831, in which Faraday explored the properties of his newest discovery, electromagnetic induction (Faraday, 1832, is the first published report). By passing a current through a coil of wire, he found that currents were induced in another coil placed a short distance away. Because the current in the first coil was known to generate magnetic forces (Oersted, 1820), this was the first demonstration of the conversion of magnetic forces into electrical forces. The induced currents were transient; they could be observed only at the instant when the current in the first coil was turned on or turned off. Having found this much, what did he do then?

Between August 29, 1831 and the first presentation of his results to the Royal Society on November 4, 1831, Faraday carried out 134 experiments to explore his discovery (see his published diary records for these dates in Faraday, 1932–1936, volume 1). In the course of these experiments, he determined the spatial relationships among the induced and inducing forces, established that ordinary bar magnets as well a...

Table of contents

• Cover Page
• Title Page
• Copyright Page
• Contents
• Preface
• PART I Contexts for Informal Reasoning
• PART II Modes and Models of Informal Reasoning
• PART III Informal Reasoning and Instruction
• Author Index
• Subject Index