Newtonianism in early Enlightenment Germany, c. 1720 to 1750: metaphysics and the critique of dogmatic philosophy

The acceptance of Newton’s ideas and Newtonianism in the early German Enlightenment is usually described as hesitant and slow. Two reasons help to explain this phenomenon. One is that those who might have adopted Newtonian arguments were critics of Wolffianism. These critics, however, drew on indigenous currents of thought, pre-dating the reception of Newton in Germany and independent of Newtonian science. The other reason is that the controversies between Wolffians and their critics focused on metaphysics. Newton’s reputation, however, was that of a mathematician, and one point, on which Wolffians and their opponents agreed, was that mathematics was of no use in the solution of metaphysical questions. The appeal to Newton as an authority in metaphysics, it was argued, was the fault of Newton’s over-zealous disciples in Britain, who tried to transform him from a mathematician into the author of a general philosophical system. It is often argued that the Berlin Academy after 1743 included a Newtonian group, but even there the reception of Newtonianism was selective. Philosophers such as Leonhard Euler were also reluctant to be labelled ‘Newtonians’, because this implied a dogmatic belief in Newton’s ideas. Only after the mid-eighteenth century is ‘Newtonianism’ increasingly accepted in the sense of a philosophical system.     

The power of images: mathematics and metaphysics in Hobbes's optics

This paper deals with Hobbes's theory of optical images, developed in his optical magnum opus, ‘A Minute or First Draught of the Optiques’ (1646), and published in abridged version in De homine (1658). The paper suggests that Hobbes's theory of vision and images serves him to ground his philosophy of man on his philosophy of body. Furthermore, since this part of Hobbes's work on optics is the most thoroughly geometrical, it reveals a good deal about the role of mathematics in Hobbes's philosophy. The paper points to some difficulties in the thesis of Shapin and Schaffer, who presented geometry as a ‘paradigm’ for Hobbes's natural philosophy. It will be argued here that Hobbes's application of geometry to optics was dictated by his metaphysical and epistemological principles, not by a blind belief in the power of geometry. Geometry supported causal explanation, and assisted reason in making sense of appearances by helping the philosopher understand the relationships between the world outside us and the images it produces in us. Finally the paper broadly suggests how Hobbes's theory of images may have triggered, by negative example, the flourishing of geometrical optics in Restoration England.     

Francesco Patrizi’s two books on space: geometry, mathematics, and dialectic beyond Aristotelian science

Francesco Patrizi was a competent Greek scholar, a mathematician, and a Neoplatonic thinker, well known for his sharp critique of Aristotle and the Aristotelian tradition. In this article I shall present, in the first part, the importance of the concept of a three-dimensional space which is regarded as a body, as opposed to the Aristotelian two-dimensional space or interval, in Patrizi’s discussion of physical space. This point, I shall argue, is an essential part of Patrizi’s overall critique of Aristotelian science, in which Epicurean, Stoic, and mainly Neoplatonic elements were brought together, in what seems like an original theory of space and a radical revision of Aristotelian physics. Moreover, I shall try to show Patrizi’s dialectical method of definition, his geometrical argumentation, and trace some of the ideas and terms used by him back to Proclus’ Commentary on Euclid. This text of Proclus, as will be shown in the second part of the article, was also important for Patrizi’s discussion of mathematical space, where Patrizi deals with the status of mathematics and redefines some mathematical concepts such as the point and the line according to his new theory of space.     

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.     

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.     

The ‘Popperian Programme’ and mathematics: Part II: From quasi-empiricism to mathematical research Programmes

In the first part of this article I investigated the Popperian roots of Lakatos's Proofs and Refutations, which was an attempt to apply, and thereby to test, Popper's theory of knowledge in a field—mathematics—to which it had not primarily been intended to apply. While Popper's theory of knowledge stood up gloriously to this test, the new application gave rise to new insights into the heuristic of mathematical development, which necessitated further clarification and improvement of some Popperian methodological maxims. In the present part I analyze this second phase in the development of Lakatos's Popperian programme in mathematics, and its connection to the methodology of scientific research programmes.     

The concept of transition and its role in Leibniz’s and Whitehead’s metaphysics of motion

Leibniz’s and Whitehead’s analyses of motion are at the heart of their metaphysical schemes. These schemes are to be considered as two blueprints of a similar metaphysical intuition that emerged during two breakthrough eras, that is, the 17th century and the beginning of the 20th century, and retained the Aristotelian idea that existence requires an active principle. The two philosophers’ attempts to elucidate this idea in the context of their analyses of motion still interact with central, longstanding questions in philosophy, in particular that concerning the ontological status of change. For both thinkers, the phenomenon of motion is an example par excellence, of the metaphysically fundamental principle of action that is required for change in the world. I focus on Leibniz’s and Whitehead’s similar understanding of the concept of transition that is inserted as an essential constitutive component of motion and ensures its status as something real.     

Intensions, belief and science: Kuhn’s early philosophical outlook (1940-1945)

Between 1940 and 1945, while still a student of theoretical physics and without any contact with the history of science, Thomas S. Kuhn developed a general outline of a theory of the role of belief in science. This theory was well rooted in the philosophical tradition of Emerson Hall, Harvard, and particularly in H. M. Sheffer’s and C. I. Lewis’s logico-philosophical works—Kuhn was, actually, a graduate student of the former in 1945. In this paper I reconstruct the development of that general outline after Kuhn’s first years at Harvard. I examine his works on moral and aesthetic issues—where he displayed an already ‘anti-Whig’ stance concerning historiography—as well as his first ‘Humean’ approach to science and realism, where his earliest concern with belief is evident. Then I scrutinise his graduate work to show how his first account of the role of belief was developed. The main aim of this paper is to show that the history of science illustrated for Kuhn the epistemic role and effects of belief he had already been theorising about since around 1941.     

The electrons of the dinosaurs and the center of the Earth: comments on D.D. Turner’s ‘The past vs. the tiny: historical science and the abductive arguments for realism’

Turner [The past vs. the tiny: Historical science and the abductive arguments for realism. Studies in History and Philosophy of Science 35A (2004) 1] claims that the arguments in favor of realism do not support with the same force both classes of realism, since they supply stronger reasons for experimental realism than for historical realism. I would like to make two comments, which should be seen as amplifications inspired by his proposal, rather than as a criticism. First, it is important to highlight that Turner’s distinction between ‘tiny’ and ‘past unobservables’ is neither excluding nor exhaustive. Second, even if we agreed with everything that Turner says regarding the arguments for realism and their relative weight in order to justify the experimental or historical version, there is an aspect that Turner does not consider and that renders historical realism less problematic than experimental realism.     

Setting up a discipline, II: British history of science and “the end of ideology”, 1931-1948

For the history of science the 1940s were a transformative decade, when salient scholars like Herbert Butterfield or Alexandre Koyré set out to shape postwar culture by promoting new standards for understanding science. Some years ago I placed these developments in a tradition of enduring arts-science tensions and the contemporary notion that previous, “scientistic”, historical practices needed to be confronted with disinterested codes of historical craft (Mayer, 2000). Here, I want to further explore the ideological dimensions of the processes through which the academic study of science became institutionalized. Butterfield’s generation of science historians moulded perception of science in highly specific ways. Whereas the scientist-historians of the 1930s put scientific innovation into its socio-economic contexts, postwar accounts portrayed the birth of modern science as an intellectual revolution. Anti-Marxism formed a defining feature of the process by which the image of scientific work as a disinterested journey of the mind came to be institutionalized. Rather than spelling the end of ideology, appointments processes in the early Cold War years reveal disagreement about what science was to be invariably coextensive with dissent about social and political order. Rather than testifying to irreconcilable conflicts between interestedness and historical craft, the work of both the 1930s and 40s speaks of surprisingly productive relations between the two.     

The rhetorical strategy of William Paley’s Natural theology (1802): Part 2, William Paley’s Natural theology and the challenge of atheism

The first part of this two-part article suggested that William Paley’s Natural theology (1802) should be viewed as the culmination of a complex psychological strategy for inculcating religious and moral sentiments. Having focused in Part 1 on Paley’s rhetoric, we now turn our attention to the philosophical part of the programme. This article attempts to settle the vexed question of how far Paley responded to the devastating critique of the teleological argument contained in Hume’s posthumously published Dialogues concerning natural religion (1779). It also identifies tensions that arose in Natural theology between the rhetorical and intellectual sides of the stratagem. In response to Erasmus Darwin’s evolutionary theories, Paley asserted that the divinely designed architecture of nature had remained unchanged since the creation. But the more he emphasized the preordained nature of providence, its effectuation through mechanical dispositions, the less room there appeared to be for particular interventions. Section 2 concentrates on Paley’s efforts to reconcile this model of a law-governed, mechanical universe, with the belief in a personal God who was active in worldly affairs. It therefore challenges the view, long unquestioned in the historical literature, that Paley’s Deity was merely a watchmaker, who had remained idle since the Creation.