Temporal naturalism (1310.8539v1)

Abstract: Two people may claim both to be naturalists, but have divergent conceptions of basic elements of the natural world which lead them to mean different things when they talk about laws of nature, or states, or the role of mathematics in physics. These disagreements do not much affect the ordinary practice of science which is about small subsystems of the universe, described or explained against a background, idealized to be fixed. But these issues become crucial when we consider including the whole universe within our system, for then there is no fixed background to reference observables to. I argue here that the key issue responsible for divergent versions of naturalism and divergent approaches to cosmology is the conception of time. One version, which I call temporal naturalism, holds that time, in the sense of the succession of present moments, is real, and that laws of nature evolve in that time. This is contrasted with timeless naturalism, which holds that laws are immutable and the present moment and its passage are illusions. I argue that temporal naturalism is empirically more adequate than the alternatives, because it offers testable explanations for puzzles its rivals cannot address, and is likely a better basis for solving major puzzles that presently face cosmology and physics. This essay also addresses the problem of qualia and experience within naturalism and argues that only temporal naturalism can make a place for qualia as intrinsic qualities of matter.

Temporal Naturalism: Reassessing Time's Role in Natural Philosophy

Lee Smolin's paper, "Temporal Naturalism," provides a comprehensive exploration of the philosophical stance of naturalism, with a focus on the notion of time and its implications for cosmological theories. Smolin confronts the established dichotomy between timeless and temporal naturalisms, arguing for the empirical adequacy and theoretical practicality of the latter. By emphasizing the significance of time in determining the nature of laws and states, Smolin proposes a radical restructuring of scientific practice, particularly in cosmology.

Smolin begins by defining temporal naturalism and distinguishing it from the prevailing view of timeless naturalism, which posits a universe as a static entity and dismisses the reality of time's passage. According to timeless naturalism, the universe can be described as a timeless mathematical object, rendering all moments, including the present, as mere illusions. In contrast, temporal naturalism embraces the reality of time and its passage, advocating for the evolution of laws and emphasizing an ongoing, dynamic cosmological process. Smolin suggests that laws should not be immutable but instead evolve, responsive to empirical evidence and experiments.

Key to Smolin's argument is the critique of the Newtonian paradigm, which separates laws from states within an isolated system. This paradigm fails when applied cosmologically, as it is unable to account for why specific laws and initial conditions govern our universe. Here, Smolin identifies the cosmological fallacy: the erroneous scaling of this paradigm to the entirety of the universe, which overlooks the uniqueness and temporal evolution inherent in cosmological phenomena. By adopting temporal naturalism, Smolin argues, science can develop a deeper understanding of the evolving nature of laws, thereby addressing the problematic aspects of cosmological choice often left unexplained by timeless naturalism.

Smolin discusses the implications of temporal naturalism for relationalism — the idea that at least some physical quantities are defined by their relations rather than intrinsic qualities. In advocating for relational properties coupled with intrinsic quantities like energy and momentum, Smolin challenges purely relational theories, suggesting that intrinsic qualities are essential for understanding physical phenomena.

Further, Smolin extends the discussion to the philosophy of qualia and consciousness. He posits that temporal naturalism can better incorporate qualia as intrinsic, non-relational properties. This stance is juxtaposed against timeless naturalism which struggles to accommodate the undeniable reality of qualia existing in the present moment. Thus, Smolin's framework not only impacts cosmology but also provides insight into the mind-body problem.

In addressing objections, Smolin argues that the reality of present moments is not incompatible with the relativity of simultaneity, a point supported by shape dynamics, a reformulation of general relativity. Moreover, temporal naturalism offers solutions to the metalaw dilemma, posing hypotheses that maintain explanatory power without leading to an infinite regress.

Smolin envisions temporal naturalism as holding the promise of resolving current cosmological crises, fostering empirical progress, and redefining philosophical debates. His perspective underscores the ongoing potential in scientific inquiry, resisting both deterministic and static interpretations. Ultimately, Smolin's paper advocates for a paradigm shift in science — one that embraces the dynamic evolution of cosmic laws and enriches our understanding of time's profound role in shaping reality.