Most contemporary philosophers call themselves “naturalists” or “physicalists”. But what do these labels really mean? What do they commit us to?
Philosopher David Papineau first puts it negatively: physicalists deny the existence of the supernatural, or of “anything spooky”. More specifically, only those things that play a causal role in the spatiotemporal world exist. And, modern physics tells us, only the physical plays such a causal role. For this reason, “abstract objects” that don’t themselves affect the physical world, such as numbers, should not be said to exist.
For much of the interview, Papineau runs through a “causal argument” to show that consciousness is physical. The argument begins with the premise that mental states have physical effects (for example, my experience of pain causes me to cry out). It also assumes that physical effects have only physical causes and that events aren’t systematically overdetermined (caused by two things at once, like a man killed by a gunshot and a bolt of lightning at once). If this is all true, it follows that mental states must themselves be physical. Papineau runs through possible ways out of this causal argument, including epiphenomenalism. In the process, he runs through a brief history of modern physics and how we came to discover that all physical effects have physical causes. He concludes with an exploration of panpsychism and “Russellian monism“, views that attempt to accept the causal argument but deny that consciousness is therefore strictly physical.
Next week: David Papineau: Mary’s Room
Interested in ontology? Check out my interview with Amie Thomasson about metaontology.
0:19: Introduction to David Papineau (sports and philosophy, metaphilosophy)
5:20 – What is naturalism?
15:15 – Do “abstract objects” exist?
19:56 – Causal argument for physicalism
26:49 – Ways out: epiphenomenalism and overdetermination
30:59 – Physical causes for physical effects: a short history of modern physics
44:39 – Quantum mechanics
48:54 – Panpsychism and Russellian monism