Studies in History and Philosophy of Science 43 (2012) 657–665 Contents lists available at SciVerse ScienceDirect Studies in History and Philosophy of Science journal homepage: www.elsevier.com/locate/shpsa Styles of reasoning: A pluralist view Otávio Bueno Department of Philosophy, University of Miami, Coral Gables, FL 33124-4670, USA article info abstract Article history: Styles of reasoning are important devices to understand scientific practice. As I use the concept, a style of Available online 28 August 2012 reasoning is a pattern of inferential relations that are used to select, interpret, and support evidence for scientific results. In this paper, I defend the view that there is a plurality of styles of reasoning: different Keywords: domains of science often invoke different styles. I argue that this plurality is an important source of dis- Style of reasoning unity in scientific practice, and it provides additional arguments in support of the disunity claim. I also Inference contrast Ian Hacking’s broad characterization of styles of reasoning with a narrow understanding that I Disunity of science favor. Drawing on examples from molecular biology, chemistry and mathematics, I argue that differences Representation in style of reasoning lead to differences in the way the relevant results are obtained and interpreted. The Imaging Hacking result is a pluralist view about styles of reasoning that is sensitive to nuances of inferential relations in scientific activity. Ó 2012 Published by Elsevier Ltd. When citing this paper, please use the full journal title Studies in History and Philosophy of Science 1. Introduction 2. Styles of reasoning as inferential frameworks Styles of reasoning play a significant role in shaping our under- Hacking conceives of styles of reasoning as broad frameworks standing of scientific activity (Hacking, 1985, 2002a, 2002b). This that govern a certain way of investigating the world. His original is, in part, due to the role they play in constituting that activity. inspiration emerged from A. C. Crombie’s Styles of Scientific Think- As I use the concept, a style of reasoning is a pattern of inferential ing in the European Tradition (Crombie, 1994), where Crombie relations that are used to select, interpret, and support evidence for develops the idea of certain styles of investigation. In an earlier pa- certain results. If we consider different domains of scientific per in 1981, Crombie described the proposal as follows: research, different styles of reasoning are often involved. The active promotion and diversification of the scientific meth- In this paper, I will illustrate how styles of reasoning shape sci- ods of late medieval and early modern Europe reflected the gen- entific practice, and I will defend the view that there is a plurality eral growth of a research mentality in European society, a of styles of reasoning: different domains of science often invoke mentality conditioned and increasingly committed by its cir- different styles of reasoning. This plurality is an important source cumstances to expect and to look actively for problems to for- of disunity in scientific activity (see Hacking, 1996; Dupré, 1993, mulate and solve, rather than for an accepted consensus & Cartwright, 1999), and it provides additional arguments in sup- without argument. The varieties of scientific method so brought port of the disunity claim. into play may be distinguished as: In order to defend this view, I will examine how different styles of reasoning are employed in different scientific fields. Drawing on examples from molecular biology, chemistry and mathematics, I (a) the simple postulation established in the mathematical will indicate how differences in style of reasoning lead to differ- sciences, ences in the way the relevant results are obtained and interpreted. (b) the experimental exploration and measurement of more The result is a pluralist view about styles of reasoning that is sen- complex observable relations, sitive to nuances of inferential relations in scientific practice. (c) the hypothetical construction of analogical models, E-mail address: [email protected] 0039-3681/$ - see front matter Ó 2012 Published by Elsevier Ltd. http://dx.doi.org/10.1016/j.shpsa.2012.07.008 658 O. Bueno / Studies in History and Philosophy of Science 43 (2012) 657–665 (d) the ordering of variety by comparison and taxonomy, main. That is precisely what is accomplished by the production of (e) the statistical analysis of regularities of populations and the phenomena by an apparatus. A class of phenomena is created and calculus of probabilities, and such phenomena need to be explained, or accounted for, by suit- (f) the historical derivation of genetic development. able models.1 As will become clear below, with the introduction of what I call narrow styles of reasoning, central to these activities is the activity The first three of these methods concern essentially the science of inferring—different ways of inferring—appropriate conclusions, of individual regularities, and the second three the science of whether they are concerned with phenomena or instruments and the regularities of populations ordered in space and time apparatuses. Some of these inferential practices invoke geometri- (Crombie, 1981, p. 284; quoted in Hacking, 2002a, p. 161). cal considerations; others rely on statistical data, while still others In Hacking’s hands, styles of reasoning remind one of Foucault’s depend on biological or physical information. In contrast, Hacking epistemes (see Foucault, 1994), due to their encompassing scope emphasizes that a style of reasoning is concerned with the produc- and their largely uncommitted character with regard to particular tion of the possibility of the relevant truth-conditions rather than theories. In this respect, styles of reasoning are significantly differ- the preservation of truth (see Hacking, 2002a, p. 168). Given the fo- ent from Kuhnian paradigms (see Kuhn, 1996) and Lakatos’ re- cus on establishing possible truth-conditions rather than guaran- search programs (see Lakatos, 1978), both of which are teeing truth preservation, one wonders to what extent talk of 2 individuated, in part, by particular theories. In Kuhn’s case, theo- ‘styles of reasoning’ is apt. An alternative, that takes seriously the ries are a central component of a paradigm: it is with reference role of reasoning, will be offered below. to a given theory that paradigms are characterized, such as the In his survey and critical examination of Hacking’s conception Newtonian paradigm or the Darwinian paradigm. Similarly, Laka- of styles of reasoning, Martin Kusch charges Hacking’s proposal tos’ research programs are characterized via the key theoretical as being unable to block epistemic relativism (Kusch, 2010). The assumptions in the hard core as well as the series of theories in epistemic relativist insists that there are no non-question begging the protective belt. arguments to favor one conception (or one style of reasoning for Hacking’s description of scientific practice tend not to empha- that matter) over another. But it seems to me that Hacking has re- size the role of theories, as his contrast between representing sources to block this form of relativism. He allows for the possibil- and intervening testifies (Hacking, 1983). With this contrast Hack- ity that the same propositions be assessed by different styles of ing was already marking the importance of shifting philosophy of reasoning. Moreover, at least in some cases, there are common science away from a theory-dominated discourse (early philosoph- standards among different styles of reasoning that allow for the ical conceptions focused on various aspects of representation) and assessment of these propositions. This is, in fact, common practice insisting on the significance of a whole class of activities, which when we use statistical analysis in laboratory sciences (statistical variously exemplify different forms of intervening. Hacking is not reasoning and laboratory reasoning being two different styles of particularly fond of theories as the key ingredient of scientific prac- reasoning). In this instance, statistical analysis provides the rele- tice, and for the most part, theories tend to play a limited role in his vant common standard that can be used to assess the propositions account of scientific activity. It is then not surprising that styles of in question. If needed, one can then adjudicate between the two reasoning are not tied to particular theories. styles of reasoning, without begging the question, by assessing Having said that, it is undeniable that styles of reasoning play a the conclusions that follow from each style given the use of the theoretical role in Hacking’s conceptualization of scientific prac- common standard. Despite the fact that different styles are in- tice. These styles allow him to systematize salient features of sci- volved, relativism need not follow. entific activity and highlight broad patterns and important Hacking explicitly allows for the combination of different styles differences within such practice. But even in this context Hacking of reasoning. The laboratory style can be thought of as a combina- stresses particular activities—rather than theoretical constructs— tion of items (b), (c), and (e) on Crombie’s list. Commenting on Pe- that underlie a style of reasoning. In his discussion of what he calls ter Galison’s trading zones—a zone of communication in which the ‘laboratory style’, Hacking notes that this style is characterized researchers who share very little common background can still ex- by change data and theoretical approximations (Galison, 1997)— Hacking notes: ‘‘The trading-zone idea will be useful in the study the building of apparatus in order to produce phenomena to of styles of reasoning when we begin to describe any inquiry that which hypothetical modeling may be true or false, but using employs several styles’’ (Hacking, 2002b, p. 184; italics added). another layer of modeling, namely models of how the apparatus Inquiries that use multiple styles and common standards provide and instruments themselves work (Hacking, 2002b, p. 184).