Philosophy Beyond Spacetime

The present volume collects essays on the philosophical foundations of quantum theories of gravity, such as loop quantum gravity and string theory. Central for philosophical concerns is quantum gravity's suggestion that space and time, or spacetime, may not exist fundamentally, but instead be a derivative entity emerging from non-spatiotemporal degrees of freedom. In the spirit of naturalized metaphysics, contributions to this volume consider the philosophical implications of this suggestion. In turn, philosophical methods and insights are brought to bear on the foundations of quantum gravity itself. For instance, the idea of functionalism, borrowed from the philosophy of mind and discussed by several chapters, exemplifies this mutual interaction the collection seeks to foster. The chapters of this collection cover three main subjects: first, the potential emergence of spacetime in various approaches to quantum gravity; second, metaphysical and epistemological considerations concerning the nature of this relation of emergence; and third, broader methodological aspects of the philosophy of quantum gravity.

An apology for conflicts between metaphysics and science in naturalized metaphysics

According to naturalized metaphysics, metaphysics should be informed by our current best science and not rely on a priori reasoning. Consequently, naturalized metaphysics tends to dismiss metaphysicians’ attempts to quarrel with science. This paper argues that naturalized metaphysics should instead welcome such conflicts between metaphysics and science. Naturalized metaphysics is not (and should not be) eliminative of metaphysics. So, if such conflicts are driven by the immediate absence in science of an answer to a metaphysical question, then the conflict should not be dismissed, but instead be received as an occasion to do (more) naturalized metaphysics. That conflicts between metaphysics and science might be beneficial for naturalized metaphysics is exemplified by the case of non-spatial theories of quantum gravity. These theories are criticized by metaphysicians who, often following David Lewis, argue that spatial distance is an indispensable fundamental element in any coherent metaphysics due to its role as the world-making relation. The resulting conflict, however, is found to be well-motivated since the non-spatial theories of quantum gravity offer no alternative world-making relation to spatial distance. Rather than dismissing this conflict, naturalized metaphysics should therefore receive the Lewisians’ resistance as a call to search for one. How this plays out as a negotiation between the scientific theory and the metaphysical question is exemplified in the last part of the paper where entanglement is proposed as an alternative world-making relation in loop quantum gravity.

A Thousand Flowers on the Road to Epistemic Anarchy: Comments on Chakravartty's Scientific Ontology

ABSTRACTI introduce the symposium on Anjan Chakravartty's Scientific Ontology by summarizing the book's main claims. In my commentary, I first challenge Chakravartty's claim that naturalized metaphysics cannot be indexed to science simpliciter. Second, I argue that there are objective truths regarding what conduces to particular epistemic aims, and that Chakravartty is therefore too permissive regarding epistemic stances and their resultant ontologies. Third, I argue that it is unclear what stops epistemic stances from having unlimited influence. Finally, I argue that Chakravartty's epistemic stance voluntarism is inadequately motivated and lacks empirical support for its psychological content.

Risk, Reward, and Scientific Ontology: Reply to Bryant, Psillos, and Slater

ABSTRACTScientific Ontology: Integrating Naturalized Metaphysics and Voluntarist Epistemology contends that ontological commitments associated with scientific inquiry are infused with philosophical commitments. Interpretations of scientific ontology involve (what I call) metaphysical inferences, and furthermore, there are different ways of making these inferences, on the basis of different but nonetheless rational epistemic stances. If correct, this problematizes any neat distinction between naturalized and other metaphysics, and dissolves any presumption of there being a uniquely correct answer to ontological questions connected to the sciences. In this paper, I consider some weighty challenges to these contentions by Amanda Bryant, Stathis Psillos, and Matthew Slater.

Super-Humeanism: The Canberra Plan for Physics

The chapter argues for a metaphysics in the vein of the Canberra plan, namely to single out a minimal, basic set of entities and then to show how everything else is located in that set by being identical with something in that set and how the propositions that describe the basic entities entail all the other true propositions. The chapter conceives the Canberra plan for the domain of the natural sciences as a naturalized metaphysics that is not committed to a priori entailment. The proposal is that the minimal set of entities is defined by the following two axioms: (1) There are distance relations that individuate simple objects, namely matter points. (2) The matter points are permanent, with the distances between them changing. Finally, the chapter explains how the Canberra plan sets a clear standard for ontological issues that go beyond the natural sciences.

Old problems for neo-positivist naturalized metaphysics

In her paper “Neo-positivist metaphysics” (Philosophical Studies, 160(1), 53–78, 2012), Alyssa Ney promises a naturalized metaphysics that is acceptable even by positivists’ – and specifically Carnap’s – standards. This neo-positivist metaphysics takes its outset in the findings of our best science and relies on them to inform a metaphysics that can avoid the dependence on linguistic frameworks that is inherent to Carnapian deflationism. Neo-positivist metaphysics attempts to sidestep these problems by inheriting its semantic credentials directly from science itself. This paper argues that such attempts are unsuccessful since science contains no resources with which to answer Carnap’s challenge either, and a science-based metaphysics is therefore just as vulnerable to Carnapian deflationism as traditional metaphysics. Consequently, neo-positivist metaphysics does not provide the promised metaphysics that can avoid Carnapian deflationism. While this conclusion focuses on Ney’s neo-positivist metaphysics, its scope includes any attempt to avoid Carnapian deflationism by a naturalized metaphysics that relies on strict deference to the findings of science. Substantial metaphysics – naturalized or not – is impossible unless or until Carnapian deflationism is refuted, and the resources for such a refutation cannot be found in naturalized metaphysics.

Metaphysics of Science as Naturalized Metaphysics

This chapter outlines a metaphysics of science in the sense of a naturalized metaphysics. It considers in the first place the interplay of physics and metaphysics in Newtonian mechanics, then goes into the issues for the metaphysics of time that relativity physics raises, shows that what one considers as the referent of quantum theory depends on metaphysical considerations, and finally explains how the stance that one takes with respect to objective modality and laws of nature shapes the options that are available for an ontology of quantum physics. In that way, this chapter seeks to make a case for a natural philosophy that treats physics and metaphysics as inseparable in the enquiry into the constitution of the world, there being neither a neo-positivist way of deducing metaphysics from the formalisms of physical theories, nor a neo-rationalist realm of investigation for metaphysics that is independent of physics.

Dispositions

Armed with the framework for thinking about naturalized metaphysics given in the previous chapters, this chapter turns to a case study in the metaphysics of science. By considering a case in some detail, various aspects of the prior framework are exemplified in a concrete way. The example considered comes from a popular arena of discussion in contemporary metaphysics of science: the attribution of a specific kind of property, dispositional properties, in giving interpretations of scientific work and practices such as explanation. The appeal to dispositional properties represents a case study of how some have attempted to use scientific knowledge and practice as a starting point or inspiration for ontological theorizing—one in which answers to certain questions, such as what stands in need of explanation and what is genuinely explanatorily powerful, figure centrally.