Edward Slowik

This essay explores the vexed issue of individual corporeal substance in Descartes' natural philosophy. Although Descartes' often referred to individual material objects as separate substances, the constraints on his definitions of matter and substance would seem to favor the opposite view; namely, that there exists only one corporeal substance, the plenum. In contrast to this standard interpretation, however, it will be demonstrated that Descartes' hypotheses make a fairly convincing case for the existence of individual material substances; and the key to this new found individuation is a long neglected set of passages in the Principles of Philosophy.

Utilizing Einstein’s comparison of General Relativity and Descartes’ physics, this investigation explores the alleged conventionalism that pervades the ontology of substantival and relationist conceptions of spacetime. Although previously discussed, namely by Rynasiewicz and Hoefer, it will be argued that the close similarities between General Relativity and Cartesian physics have not been adequately treated in the literature—and that the disclosure of these similarities bolsters the case for a conventionalist interpretation of spacetime ontology.

This essay explores the use of platonist and nominalist concepts, derived from the philosophy of mathematics and metaphysics, as a means of elucidating the debate on spacetime ontology and the spatial structures endorsed by scientific realists. Although the disputes associated with platonism and nominalism often mirror the complexities involved with substantivalism and relationism, it will be argued that a more refined three-part distinction among platonist/nominalist categories can nonetheless provide unique insights into the core assumptions that underlie spatial ontologies, but it also assists in critiquing alternative uses of nominalism, platonism, and both ontic and epistemic structural realism.

This essay critically examines Joseph Rouse's arguments against, what he dubs, the "legitimation project", which are the attempts to delimit and justify the scientific enterprise by means of global, "a priori" principles. Stipulating that a more adequate picture of science can be obtained by viewing it as a continuously transforming pattern of situated activities, Rouse believes that only by refocusing attention upon the actual practice of science can philosophers begin to detach themselves from the irresolvable epistemological problems that have remained the primary byproduct of the traditional philosophical approach. On closer inspection, however, Rouse's project appears susceptible to the criticism that it is either too relativistic to do the work he envisioned for it, or that it participates in the very same legitimation venture that it was intended to replace (in addition to its own brand metaphysical/epistemological problems). This unexpected outcome, moreover, suggests that such legitimation projects may be an integral component of the very practice of science, contrary to Rouse estimate.

This paper investigates the question of, and the degree to which, Newton’s theory of space constitutes a third-way between the traditional substantivalist and relationist ontologies, i.e., that Newton judged that space is neither a type of substance/entity nor purely a relation among such substances. A non-substantivalist reading of Newton has been famously defended by Howard Stein, among others; but, as will be demonstrated, these claims are problematic on various grounds, especially as regards Newton’s alleged rejection of the traditional substance/accident dichotomy concerning space. Nevertheless, our analysis of the metaphysical foundations of Newton’s spatial theory will strive to uncover its unique and innovative characteristics, most notably, the distinctive role that Newton’s “immaterialist” spatial ontology plays in his dynamics

This paper examines Descartes' problematic relational theory of motion, especially when viewed within the context of his dynamics, the Cartesian natural laws. The work of various commentators on Cartesian motion is also surveyed, with particular emphasis placed upon the recent important texts of Garber and Des Chene. In contrast to the methodology of most previous interpretations, however, this essay employs a modern "spacetime" approach to the problem. By this means, the role of dynamics in Descartes' theory, which has often been neglected in favor of kinematic factors, is shown to be central to finding a solution to the puzzle of Cartesian motion.

Do theories of quantum mechanics and quantum gravity require spacetime to be a basic, ground level feature, or can spacetime be seen as an emergent element of these theories? While several commentators have raised serious doubts about the prospects of forgoing the standard spacetime backdrop, it will be argued that a defense of these emergent spacetime interpretations of quantum mechanics and quantum gravity hypotheses can be made, whether as an inference to the best explanation or using another strategy. Furthermore, the idea that space and time can arise from a quite different, non-spatiotemporal level of reality will be shown to have various historical precedents, especially in the seventeenth and eighteenth centuries, a realization that may help dispel some of the mystery associated with these types of hypotheses.

This essay explores theories of place, or lived-space, as regards the role of objectivity and the problem of relativism. As will be argued, the neglect of mathematics and geometry by the lived-space theorists, which can be traced to the influence of the early phenomenologists, principally the later Husserl and Heidegger, has been a major contributing factor in the relativist dilemma that afflicts the lived-space movement. By incorporating various geometrical concepts within the analysis of place, it is demonstrated that the lived-space theorists can gain a better insight into the objective spatial relationships among individuals and within groups—and, more importantly, this appeal to mathematical content need not be construed as undermining the basic tenants of the lived-space approach.

In the Principles of Philosophy, Descartes attempts to explicate the well-known phenomena of varying bodily size through an appeal to the concept of "solidity," a notion that roughly corresponds to our present-day concept of density. Descartes' interest in these issues can be partially traced to the need to define clearly the role of matter in his natural laws, a problem particularly acute for the application of his conservation principle. Specifically, since Descartes insists that a body's "quantity of motion," defined as the product of its "size" and speed, is conserved in all material interactions, it is imperative that he explain how solidity influences the magnitude of this force. As a means of resolving this problem, Descartes postulated an idealized condition of "perfect solidity" which correlates a body's "agitation" force (a forerunner of Newton's concept of non-accelerating, or "inertial" motion) with the interplay of its volume, surface area, and composition of minute particles. This essay explores this often misunderstood aspect of Descartes' physics, as well as the special function of idealized conditions in his collision rules. Contrary to those commentators who regard "perfect solidity" as a stipulation on bodily impact, this notion, it will be argued, is primarily concerned with the internal composition of macroscopic bodies, and only indirectly with their collision characteristics. Along the way, many of Descartes' hypotheses will be shown to display a level of sophistication and intricacy that, despite their essential incompatibility, belie several of the common misconceptions of Cartesian science.

This paper examines the status of explanation in the natural sciences and ethics by focusing on the important role of empirical evidence and theoretical properties. As a means of exploring these issues, the debate between Nicholas Sturgeon and Gilbert Harman will serve as a central point in the discussion, since Sturgeon has provided several arguments against Harman's attempt to draw a distinction between scientific and moral explanation. Specifically, Sturgeon holds that the special function of observation and testing, which we commonly believe to be relevant only in science, can be applied to moral cases with equal justification. Overall, Sturgeon's arguments will be exposed as deficient in several respects, which is an aspect of this debate often overlooked.

This essay explores two of the more neglected hypotheses that comprise, or supplement, Descartes’ relationalist doctrine of bodily motion. These criteria are of great importance, for they would appear to challenge Descartes’ principal judgment that motion is a purely reciprocal change of a body’s contiguous neighborhood. After critiquing the work of the few commentators who have previously examined these forgotten hypotheses, mainly, D. Garber and M. Gueroult, the overall strengths and weaknesses of Descartes’ supplementary criteria will be assessed. Overall, despite their ingenuity, it will be demonstrated that Descartes’ criteria cannot rescue his brand of natural laws from the inherent limitations of his strong relational account of motion.

This paper investigates Newton’s ontology of space in order to determine its commitment, if any, to both Cambridge neo-Platonism, which posits an incorporeal basis for space, and substantivalism, which regards space as a form of substance or entity. A non-substantivalist interpretation of Newton’s theory has been famously championed by Howard Stein and Robert DiSalle, among others, while both Stein and the early work of J. E. McGuire have downplayed the influence of Cambridge neo-Platonism on various aspects of Newton’s own spatial hypotheses. Both of these assertions will be shown to be problematic on various grounds, with special emphasis placed on Stein’s influential case for a non-substantivalist reading. Our analysis will strive, nonetheless, to reveal the unique or forward-looking aspects of Newton’s approach, most notably, his critical assessment of substance ontologies, that help to distinguish his theory of space from his neo-Platonic contemporaries and predecessors

This paper investigates Hume's theory of the perception of spatial magnitude or size as developed in the _Treatise<D>, as well as its relation to his concepts of space and geometry. The central focus of the discussion is Hume's espousal of the 'composite' hypothesis, which holds that perceptions of spatial magnitude are composed of indivisible sensible points, such that the total magnitude of a visible figure is a derived by-product of its component parts. Overall, it will be argued that a straightforward reading of this hypothesis fails to do full justice to the complexity of Hume's theory of spatial perception and geometry, and that a more adequate treatment must also admit an important role for the more direct process of spatial magnitude perception which he dubs 'intuition'

In De gravitatione, Newton contends that Descartes' physics is fundamentally untenable since the "fixed" spatial landmarks required to ground the concept of inertial motion cannot be secured in the constantly changing Cartesian plenum. Likewise, it is has often been alleged that the collision rules in Descartes' Principles of Philosophy undermine the "relational" view of space and motion advanced in this text. This paper attempts to meet these challenges by investigating the theory of connected gears (or "kinematics of mechanisms") for a potential Cartesian method of positing the permanent reference frames necessary to uphold Descartes' conservation law for the quantity of motion. In particular, the insights gained from an examination of the kinematics of mechanisms will provide the Cartesian with much needed resources to counter the two threats posed above.

This essay develops a interpretation of Leibniz’ theory of motion that strives to integrate his metaphysics of force with his doctrine of the equivalence of hypotheses, but which also supports a realist, as opposed to a fully idealist, interpretation of his natural philosophy. Overall, the modern approaches to Leibniz’ physics that rely on a fixed spacetime backdrop, classical mechanical constructions, or absolute speed, will be revealed as deficient, whereas a more adequate interpretation will be advanced that draws inspiration from an invariantist conception of reality and recent non-classical theories of physics.

This essay explores the benefits of utilizing non-scientific examples and analogies in teaching philosophy of science courses. These examples can help resolve two basic difficulties faced by most instructors, especially when teaching lower-level courses: first, they can prompt students to take an active interest in the class material, since the examples will involve aspects of the culture well-known, or at least more interesting, to the students; and second, these familiar, less-threatening examples will lessen the students' collective anxieties and open them up to learning the material more easily. To demonstrate this strategy of constructing and employing non-scientific examples, a lengthy analogy between musical styles and Kuhn's theory of scientific revolutions is developed.

This essay explores the role of God’s omnipresence in Newton’s natural philosophy, with special emphasis placed on how God is related to space. Unlike Descartes’ conception, which denies the spatiality of God, or Gassendi and Charleton’s view, which regards God as completely whole in every part of space, it is argued that Newton accepts spatial extension as a basic aspect of God’s omnipresence. The historical background to Newton’s spatial ontology assumes a large part of our investigation, but with attention also focused on the details of Newton’s unique approach to these traditional Scholastic conceptions.

This essay explores the possibility of constructing a structural realist interpretation of spacetime theories that can resolve the ontological debate between substantivalists and relationists. Drawing on various structuralist approaches in the philosophy of mathematics, as well as on the theoretical complexities of general relativity, our investigation will reveal that a structuralist approach can be beneficial to the spacetime theorist as a means of deflating some of the ontological disputes regarding similarly structured spacetimes.

This article investigates the problem of the identity of the parts of space in Newton’s natural philosophy, as well as the holistic or structuralist nature of Newton’s ontology of space. Additionally, this article relates the lessons reached in this historical and philosophical investigation to analogous debates in contemporary space-time ontology. While previous contributions, by Nerlich, Huggett, and others, have proven to be informative in evaluating Newton’s claims, it will be argued that the underlying goals of Newton’s views have largely eluded prior analysis and that Newton’s approach is similar, and lends support, to several current structuralist trends in the conception of space-time ontology.

This paper explores the Cartesian physics of circular motion, in particular, the long-standing puzzle concerning the possible role of a circular inertial concept in Descartes' theories. Although some commentators have claimed that Descartes' famous "rotating sling" examples favor a rotational component of "striving" towards motion, and that this aspect of his project constitutes a form of inertial thinking, it will be argued that a much stronger case for a Cartesian brand of rotational inertial motion can be constructed from a little-known correspondence, the letter to Ciermans, dated 1638.

This paper attempts to resolve the puzzle associated with the non-spatiality of monads by investigating the possibility that Leibniz employed a version of the extension of power doctrine, a Scholastic concept that explains the relationship between immaterial and material beings. As will be demonstrated, not only does the extension of power doctrine lead to a better understanding of Leibniz’ reasons for claiming that monads are non-spatial, but it also supports those interpretations of Leibniz’ metaphysics that accepts the real extension of bodies.

This essay examines the metaphysical foundation of Leibniz’s theory of space against the backdrop of the subtantivalism/relationism debate and at the ontological level of material bodies and properties. As will be demonstrated, the details of Leibniz’ theory defy a straightforward categorization employing the standard relationism often attributed to his views. Rather, a more careful analysis of his metaphysical doctrines related to bodies and space will reveal the importance of a host of concepts, such as the foundational role of God, the holism of both geometry and the material world’s interconnections, and the viability and adequacy of a property theory in characterizing his natural philosophy of space.