Mary has lived her entire life in a black and white room. In that room, she learned everything there is to know about the neurophysiology of perception. She knows everything that happens in the brain when a person sees a blue sky. One day, Mary leaves the black and white room and sees the blue sky. Has Mary learned something new?
Frank Jackson posed this famous thought experiment as a challenge to physicalists, such as David Papineau, who argue that qualitative experiences are identical to brain states. If this is really so, the argument goes, Mary isn’t learning anything new, since she already knew everything about the relevant brain states. But she does seem to learn something new: what it’s actually like to see blue. In this interview, Papineau addresses this challenge and explains why he thinks that, despite our intuitions to the contrary, qualitative experiences are simply neural states under a different description.
1:20 – Mary’s room
3:21 – Mary discovers a new concept for the same thing
6:46 – Phenomenal concepts as revelatory
10:37 – Russellian monism again
17:46 – Being like something
19:47 – Ontology of different concepts
32:36 – Aspect of the brain state?…
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.…
That sentence – called “Moore’s problem,” after its creator G.E. Moore – is interesting because it is a case of something which can be true and yet is impossible to believe. It’s perfectly possible for it to be raining and for me not to believe that it is raining. In fact, it’s happened many times. Yet, I can never believe it as it is happening.
Moore’s problem is not a very serious one. Fully accounting for it is a tricky logical exercise, but it is obvious that there is no real problem. You can’t both believe that it’s raining and believe that you don’t believe that it’s raining. Beliefs just don’t work that way.
Moore’s problem points to a broader issue, however: philosophical positions that can be true but cannot be believed.
Consider Freudianism: the belief that it is our primal, unconscious desires that govern our rationality. If this is, in fact, true, then whatever reasoning we used in order to reach the conclusion of Freudianism must have been an expression of our primal, unconscious desires. This means we have no reason to trust that reasoning in the first place. Our belief in Freudianism undercuts itself.
Or Marxism: the belief that class superstructures govern our rationality. If this is true, then whatever reasoning we use to come to Marxism is an expression of whatever class superstructures we are governed by. We have no reason to think that reasoning reliable. As with Freudianism, belief in Marxism becomes self-defeating.…