The metaphysics of fundamentality, infinitism and multiverse cosmology

This video is part of the PROTEUS project that has received funding from the European Research Council (ERC) under the Horizon 2020 research and innovation programme (Grant agreement No. 758145)

Abstract

There is an interesting, and at least partly unexplored, connection between the recently flourishing debate in metaphysics concerning fundamentality and the structure of reality, and the host of hypotheses and models that have been, and keep being, devised by physicists in order to account for the fundamental nature of the microscopic domain and of the universe as a whole. Here, I will look at the prospects for ‘non-standard’ metaphysical views of reality in connection to some ideas in contemporary cosmology. In particular, I will first provide an outline and (limited) defense of so-called ‘metaphysical infinitism’ – the view according to which there is no (or at least need not be a) ‘fundamental level’, and accepting infinite chains of dependence may provide better explanations than those afforded by foundationalism. While doing this, I will also differentiate various forms of infinitism.  Based on this, I will, more briefly, look at some recent proposals in cosmology, according to which the development of our universe since the Big Bang becomes just a chapter in a longer, possibly infinite, story; and/or  our universe is merely a part of a more complex, possibly infinite, multiverse structure. Among other things, these multiverse models are said to provide a natural solution of fine-tuning type of puzzles, as well as to ‘explain away’ the very idea of an ungrounded beginning. I will show that this (alleged) explanatory advantage is due to the fact that multiverse cosmologies invite us to question exactly those philosophical presuppositions that are at work in the context of metaphysical foundationalism and are dropped by infinitists. Then, I will consider the all-important question whether the cosmological explananda truly require infinitely many universes or ‘just’ a large plurality of them. Besides that of providing an introduction to a specific debate in contemporary metaphysics and metaphysics of science, this talk has the more general aim of lending support to a sophisticated form of philosophical naturalism – one whereby, rather than being replaced by science or made strongly dependent on it, metaphysics enters into a virtuous, egalitarian two-way relationship with it.