Descartes’s changing mind

Descartes is always concerned about knowledge. However, the Galileo affair in 1633, the reactions to his Discourse on method, and later his need to reply to objections to his Meditations provoked crises in Descartes’s intellectual development the import of which has not been sufficiently recognized. These events are the major reasons why Descartes’s philosophical position concerning how we know and what we may know is radically different at the end of his life from what it was when he began. We call this later position Descartes’s epistemic stance and contrast it with his earlier methodological, metaphysical realism. Yet Descartes’s epistemic views cannot be separated from other aspects of his work, for example, his views concerning God, causality, metaphysics, and the nature of science. A further meta-implication is that serious errors await any scholar who cites early Cartesian texts in support of late Cartesian positions, or who uses later texts in conjunction with early ones to support a reading of Descartes’s philosophy.     

Scientific realism bit by bit: part I. Kitcher on reference

In this paper, I consider Kitcher’s (1993) account of reference for the expressions of past science. Kitcher’s case study is of Joseph Priestley and his expression ‘dephlogisticated air’. There is a strong intuitive case that ‘dephlogisticated air’ referred to oxygen, but it was underpinned by very mistaken phlogiston theory, so concluding either that dephlogisticated air referred straightforwardly or that it failed to refer both have unpalatable consequences. Kitcher argues that the reference of such terms is best considered relative to each token—some tokens refer, and others do not. His account thus relies crucially on how this distinction between tokens can be made good—a puzzle I call the discrimination problem. I argue that the discrimination problem cannot be solved. On any reading of Kitcher’s defence of the distinction, the grounds provided are either insufficient or illegitimate. On the first reading, Kitcher violates the principle of humanity by making Priestley’s referential success a matter of the mental contents of modern speakers. The second reading sidesteps the problem of beliefs by appealing to mind-independent facts, but I argue that these are insufficient to achieve reference because of the indeterminacy introduced by the qua problem. On the third and final reading, Priestley’s success is given by what he would say in counterfactual circumstances. I argue that even if there are facts about what Priestley would say, and there is reason for doubt, there is no motivation to think that such facts determine how Priestley referred in the actual world.     

From centripetal forces to conic orbits: a path through the early sections of Newton’s Principia

In this study, we test the security of a crucial plank in the Principia’s mathematical foundation, namely Newton’s path leading to his solution of the famous Inverse Kepler Problem: a body attracted toward an immovable center by a centripetal force inversely proportional to the square of the distance from the center must move on a conic having a focus in that center. This path begins with his definitions of centripetal and motive force, moves through the second law of motion, then traverses Propositions I, II, and VI, before coming to an end with Propositions XI, XII, XIII and this trio’s first corollary. To test the security of this path, we answer the following questions. How far is Newton’s path from being truly rigorous? What would it take to clarify his ambiguous definitions and laws, supply missing details, and close logical gaps? In short, what would it take to make Newton’s route to the Inverse Kepler Problem completely convincing? The answer is very surprising: it takes far less than one might have expected, given that Newton carved this path in 1687.     

‘Physics and fashion’: John Tyndall and his audiences in mid-Victorian Britain

This paper explores how the physicist John Tyndall transformed himself from humble surveyor and schoolmaster into an internationally applauded icon of science. Beginning with his appointment as Professor of Natural Philosophy at the Royal Institution in 1853, I show how Tyndall’s worries about his social class and Irish origins, his painstaking attention to his lecturing performance and skilled use of the material and architectural resources of the Royal Institution were vital to his eventual success as a popular expositor and ambassador for science. Secondly I explore the implications of Tyndall’s ‘popularity’ with respect to debates over the meaning and value of scientific ‘popularisation’. In support of recent work challenging diffusionist models of science communication, I show how Tyndall’s interactions with his audiences illustrate the symbiotic relationship between producer and consumer of ‘popular’ science. By examining the views of Tyndall’s critics—notably the ‘North British’ group of physicists—and his defenders and rivals in the domain of popular scientific lecturing, I show that disputes over Tyndall’s authority reflected anxieties about what constituted popular science and the transient boundaries between instruction and entertainment. The term ‘popularisation’ enjoyed many different uses in these debates, not least of all as a rheorical device with which to either exalt or destroy a scientist’s credibility.     

Cartesian causation: body–body interaction, motion, and eternal truths

There is considerable debate among scholars over whether Descartes allowed for genuine body–body interaction. I begin by considering Michael Della Rocca’s recent claim that Descartes accepted such interaction, and that his doctrine of the creation of the eternal truths indicates how this interaction could be acceptable to him. Though I agree that Descartes was inclined to accept real bodily causes of motion, I differ from Della Rocca in emphasizing that his ontology ultimately does not allow for them. This is not the end of the story however, since two of Descartes’s successors offered incompatible ways of developing his conflicted account of motion. I contrast the occasionalist view of Nicolas Malebranche that changes in motion derive directly from divine volitions with the non-occasionalist claim of Pierre-Sylvain Regis that such changes derive from a nature distinct from God. In light of Della Rocca’s interpretation, it is noteworthy that the issue of eternal truths is relevant to both alternative accounts. Indeed, Regis took the doctrine that such truths are created to provide crucial support for his alternative to an occasionalist account of body–body interaction. What does not help Della Rocca, however, is that Regis’s view of motion requires a fundamental revision of Descartes’s ontology.     

History of Science through Koyré's Lenses

Alexandre Koyré was one of the most prominent historians of science of the twentieth century. The standard interpretation of Koyré is that he falls squarely within the internalist camp of historians of science—that he focuses on the history of the ideas themselves, eschewing cultural and sociological interpretations regarding the influence of ideologies and institutions on the development of science. When we read what Koyré has to say about his historical studies (and most of what others have said about them), we find him embracing and championing this Platonic view of his work. Ultimately I think this interpretation of Koyré's history of science is lopsided and in need of correction. I claim, rather, that a careful reading of Koyré's work suggests that a tension exists between internal and external methodological considerations. The external considerations stem from Koyré's commitment to the unity of human thought and the influence he admits that the ‘transscientifiques’ (philosophy, metaphysics, religion) have on the development of science. I suggest in conclusion then, that if we are to put a philosophical label on his work, rather than ‘Platonist’, as has been the custom, ‘Hegelian’ makes a better fit.     

Collecting airs and ideas: Priestley’s style of experimental reasoning

It has often been claimed that Priestley was a skilful experimenter who lacked the capacities to analyze his own experiments and bring them to a theoretical closure. In attempts to revise this view some scholars have alluded to Priestley’s ‘synoptic’ powers while others stressed the contextual role of British Enlightenment in understanding his chemical research. A careful analysis of his pneumatic reports, privileging the dynamics of his experimental practice, uncovers significant yet neglected aspects of Priestley’s science. By focusing on his early experimental conduct and writing on nitrous air, I demonstrate how his methodological and rhetorical devices, far from being consequences of compulsive writing or theoretical naïveté, were deeply entwined with his chemical research. I employ the notion of ‘style of experimental reasoning’ (SER)—derived from A. C. Crombie and I. Hacking—to shed light on the intersection at which Priestley’s unique method, literary style, and epistemology converged to generate scientific knowledge. Establishing Priestley’s SER advances a finer understanding of the interactive character of his pneumatic experimentalism, peculiar dimensions of which have evaded both traditional as well as revisionist scholarship, thus infusing the longstanding historiographic debate over his scientific merits.     

Science, truth and history, part II. Metaphysical bolt-holes for the Sociology of Scientific Knowledge?

Historians of science have frequently sought to exclude modern scientific knowledge from their narratives. Part I of this paper, published in the previous issue, cautioned against seeing more than a literary preference at work here. In particular, it was argued—contra advocates of the Sociology of Scientific Knowledge (SSK)—that a commitment to epistemological relativism should not be seen as having straightforward historiographical consequences. Part II considers further SSK-inspired attempts to entangle the currently fashionable historiography with particular positions in the philosophy of science. None, I argue, is promising. David Bloor’s proposed alliance with scientific realism relies upon a mistaken view of contrastive explanation; Andrew Pickering’s appeal to instrumentalism is persuasive for particle physics but much less so for science as a whole; and Bruno Latour’s home-grown metaphysics is so bizarre that its compatibility with SSK is, if anything, a further blow to the latter’s plausibility.     

Mach and Hertz’s mechanics

The place of Heinrich Hertz’s The principles of mechanics in the history of the philosophy of science is disputed. Here I critically assess positivist interpretations, concluding that they are inadequate.There is a group of commentators who seek to align Hertz with positivism, or with specific positivists such as Ernst Mach, who were enormously influential at the time. Max Jammer is prominent among this group, the most recent member of which is Joseph Kockelmans. I begin by discussing what Hertz and Mach had to say about one another, and I specify certain respects in which their views are indeed similar. I then go on to detail their differences, looking at Hertz’s attitude to the atomic theory, to the mechanical world-view, to simplicity, to unobservables and metaphysics, and his objections to Newtonian forces. I conclude that the positivist interpretation of Hertz’s mechanics significantly overplays its similarities to Mach’s views.     

Pierre Duhem’s virtue epistemology

Duhem’s concept of ‘good sense’ is central to his philosophy of science, given that it is what allows scientists to decide between competing theories. Scientists must use good sense and have intellectual and moral virtues in order to be neutral arbiters of scientific theories, especially when choosing between empirically adequate theories. I discuss the parallels in Duhem’s views to those of virtue epistemologists, who understand justified belief as that arrived at by a cognitive agent with intellectual and moral virtues, showing how consideration of Duhem as a virtue epistemologist offers insights into his views, as well as providing possible answers to some puzzles about virtue epistemology. The extent to which Duhem holds that the intellectual and moral virtues of the scientist determine scientific knowledge has not been generally noticed.     

Symmetry, asymmetry, and the real possibility of radical change: reply to Kochan

In his critique of my book Heidegger and Marcuse, Jeff Kochan (2006) asserts that I am committed to the possibility of private knowledge, transcendent truths, and individualism. In this reply I argue that he has misinterpreted my analysis of the Challenger disaster and Marcuse’s work. Because I do not dismiss Roger Boisjoly’s doubts about the Challenger launch, Kochan believes that I have abandoned a social concept of knowledge for a reliance on the private knowledge of a single individual. In fact, I consider Boisjoly’s observations just as social, if not as scientific, as the results of rigorous scientific study. Kochan’s reliance on a principle of symmetry derived from science studies to explain such politically charged technological controversies tends to mask the role of power and ideology in social life. Kochan interprets Marcuse as a failed Heideggerian who regresses from Heidegger’s social conception of human being to traditional individualism. I am accused of sharing this view. This interpretation overlooks the importance of the Hegelian–Marxist category of ‘real possibility’ in Marcuse’s work and so mistakes his critique of conformist politics for individualist romanticism. Marcuse always attempted to ground radical opposition in a community of struggle without abandoning the heritage of a long critical tradition. This view I willingly share.     

The Passions of the soul and Descartes’s machine psychology

Descartes developed an elaborate theory of animal physiology that he used to explain functionally organized, situationally adapted behavior in both human and nonhuman animals. Although he restricted true mentality to the human soul, I argue that he developed a purely mechanistic (or material) ‘psychology’ of sensory, motor, and low-level cognitive functions. In effect, he sought to mechanize the offices of the Aristotelian sensitive soul. He described the basic mechanisms in the Treatise on man, which he summarized in the Discourse. However, the Passions of the soul contains his most ambitious claims for purely material brain processes. These claims arise in abstract discussions of the functions of the passions and in illustrations of those functions. Accordingly, after providing an intellectual context for Descartes’s theory of the passions, especially by comparison with that of Thomas Aquinas, I examine its ‘machine psychology’, including the role of habituation and association. I contend that Descartes put forth what may reasonably be called a ‘psychology’ of the unensouled animal body and, correspondingly, of the human body when the soul does not intervene. He thus conceptually distinguished a mechanistically explicable sensory and motor psychology, common to nonhuman and human animals, from true mentality involving higher cognition and volition and requiring (in his view) an immaterial mind.     

Saving the Strong Programme: a critique of Stephen Kemp’s recent paper

In this paper I intend to discuss some of the views put forward by Stephen Kemp in his recent critique of the Strong Program (Kemp, 2005). In particular I will try to defend David Bloor’s SSK against the charge of weak idealism brought up by Stephen Kemp in his paper. The widely held accusation, namely, according to which the social constructionist approach to scientific knowledge is strongly idealist, is already rejected by Kemp himself. He argues, however that Bloor’s attempts to divert the charge of idealism from the Strong Programme were not successful with respect to the kind of idealism that Kemp calls ‘weak idealism’, that is, treating scientific discourse as free-floating and unrelated to the world of things. I intend to argue that Kemp’s charges are unfounded when levelled at Bloor’s views on meaning and reference. Kemp deals with two issues of the Bloorian program: with the social constructionist approach to concepts as self-referential social institutions, and with the actor/analyst distinction introduced by the Strong Programmers. I will focus only on the first issue in my paper.     

Weyl’s ‘agens theory’ of matter and the Zurich Fichte

This paper investigates Hermann Weyl’s reception of philosophical concepts stemming from the German Idealist Johann Gottlieb Fichte. In particular, Weyl’s ‘agens theory’ of matter, which he held around 1925, will be looked at. In the extant literature, the—admittedly also important—influence of Husserl on Weyl has mainly been addressed. Thus, apart from investigating some detailed Fichtean inheritances in Weyl’s concepts of causality, chance and continuity, the general difference which Weyl saw between the philosophies of Fichte and Husserl will also be discussed. For Weyl this is above all a difference between an active constructivism and a rather passive phenomenological seeing (Schau). Further, the paper shows in some detail the way Weyl was drawn into a certain reading of Fichte by his Zurich colleague, the philosopher Fritz Medicus. The methodological frame of the paper is that of Konstellationsforschung, a historical and systematic approach which proves to be particularly fruitful when investigating a (broadly speaking) German Idealist context and which allows special attention to be given to the acting subjects within the constellation under investigation. Conversely, Weyl’s agens theory suggests amendments to this methodology.     

The intelligibility of motion and construction: Descartes’ early mathematics and metaphysics, 1619-1637

I argue for an interpretation of the connection between Descartes’ early mathematics and metaphysics that centers on the standard of geometrical intelligibility that characterizes Descartes’ mathematical work during the period 1619 to 1637. This approach remains sensitive to the innovations of Descartes’ system of geometry and, I claim, sheds important light on the relationship between his landmark Geometry (1637) and his first metaphysics of nature, which is presented in Le monde (1633). In particular, I argue that the same standard of clear and distinct motions for construction that allows Descartes to distinguish ‘geometric’ from ‘imaginary’ curves in the domain of mathematics is adopted in Le monde as Descartes details God’s construction of nature. I also show how, on this interpretation, the metaphysics of Le monde can fruitfully be brought to bear on Descartes’ attempted solution to the Pappus problem, which he presents in Book I of the Geometry. My general goal is to show that attention to the standard of intelligibility Descartes invokes in these different areas of inquiry grants us a richer view of the connection between his early mathematics and philosophy than an approach that assumes a common method is what binds his work in these domains together.     

Thomas Reid and the problem of induction: from common experience to common sense

By the middle of the eighteenth century the new science had challenged the intellectual primacy of common experience in favor of recondite, expert and even counter-intuitive knowledge increasingly mediated by specialized instruments. Meanwhile modern philosophy had also problematized the perceptions of common experience — in the case of David Hume this included our perception of causal relations in nature, a fundamental precondition of scientific endeavor.In this article I argue that, in responding to the ‘problem of induction’ as advanced by Hume, Reid reformulated Aristotelian foundationalism in distinctly modern terms. An educator and mathematician self-consciously working within the framework of the new science, Reid articulated a philosophical foundation for natural knowledge anchored in the human constitution and in processes of adjudication in an emerging modern public sphere of enlightened discourse. Reid thereby transformed one of the bases of Aristotelian science — common experience — into a philosophically and socially justified notion of ‘common sense’. Reid's intellectual concerns had as much to do with the philosophy of science as they did with moral philosophy or epistemology proper, and were bound up with wider social and scientific changes taking place in the early modern period.     

‘Lord only of the ruffians and fiends’? William Whewell and the plurality of worlds debate

By the middle of the nineteenth century, the opinion of science, as well as of philosophy and even religion, was, at least in Britain, firmly in the camp of the plurality of worlds, the view that intelligent life exists on other celestial bodies. William Whewell, considered an expert on science, philosophy and religion (among other areas), would have been expected to support this position. Yet he surprised everyone in 1853 by publishing a work arguing strongly against the plurality view. This was even stranger given that he had endorsed pluralism twenty years earlier in his contribution to the Bridgewater Treatises. In this paper I show that the shift in Whewell’s view was motivated by three factors: the influence of Richard Owen’s theory of archetypes on Whewell’s view of the argument from design, and Whewell’s perception of the need to strengthen such arguments in light of evolutionary accounts of human origins; important developments in his view of philosophy and his role as a scientific expert; and new findings in astronomy. An examination of the development of Whewell’s position provides a lens through which we can view the interplay of theology, philosophy and science in the plurality of worlds debate.     

Interactional expertise and embodiment

In this four part exchange, Evan Selinger starts by stating that Collins’s empirical evidence in respect of linguistic socialization and its bearing on artificial intelligence and expertise is valuable; it advances philosophical and sociological understanding of the relationship between knowledge and language. Nevertheless, he argues that Collins mischaracterizes the data under review and thereby misrepresents how knowledge is acquired and understates the extent to which expert knowers are embodied. Selinger reconstructs the case for the importance of the body in the initial acquisition of language and challenges Collins to show how a disembodied entity could become fluent in any language at all.Collins responds by accepting that his approach does not demonstrate quite as much about the irrelevance of the body as he thought it did but that even though he accepts all of Selinger’s claims, ‘the body’ as needed by the philosophical approach set out by Selinger is still a vestigial thing. Collins’s main point, however, is that the philosophical view of the body—the world is divided into embodied agents and unembodied entities—distracts attention from the more interesting empirically researchable question of how the ability to become socialized diminishes, if it does, as the body become more and more minimal. The right research question is not about whether a person can extrapolate from minimal sensory input but how much extrapolation is possible under different circumstances and how it is done.Dreyfus, having seen the whole of the exchange so far, agrees that both have a point but argues that Collins’s approach still misses the well established importance of bodily engagement for full understanding.Collins responds to this by trying to set out more clearly the position associated with the idea of interactional expertise.     

Response to one point in Gingras’s review of Gravity’s shadow

Yves Gingras says of my book Gravity’s shadow that it is too long, the style is poor, and in its 870 pages there is nothing new that is not to be regretted. Gingras’s purity of vision would be a cause for congratulation were it not for the appalling implications of one of his claims. For the sake of the future of social science—indeed for the sake of the future of civilisation—it is impossible to leave unchallenged the idea that respondents, who don’t like to see their use of data questioned, are to be commended when they withhold those data from public scrutiny.     

The significance of the Barrovian Case

The Barrovian Case is a technical problem, hitherto unsolved, involving either a double convex lens or a concave mirror. The problem, due to Isaac Barrow and reported by Berkeley in his New theory of vision, is that what is seen in certain instances with these devices seems to violate historically important principles of optics. One is the ‘ancient principle’ of Euclid that the object should be seen at the intersection of the refracted (or reflected) ray with the perpendicular of incidence; the other is the principle attributed to Kepler that the perceived distance of an object varies indirectly with the divergence of the rays it sends to the eye. The most obvious difficulty is that the object should appear, impossibly, behind the eye. As it happens, despite some strong claims that have been made about the significance of the problem, the principles generating it no longer have the centrality in optics they were once thought to have. But even accepting them, the problem can be solved by viewing it as an instance, albeit a very complicated one, of the classical problem of the relativity of sense perception.