Suppose that Mary lives in a universe whose physics is radically different from ours. She loves mathematics and is amazingly good at it. She has very little knowledge of biology, beyond what little superficial information she can glean by turning her eye-stalks on herself while spending all her life suspended in a vortex of Z-force. One day, she is given a complete description of the physical state of the laws of our universe and of the physical arrangement of matter in the Solar System over the past billion ears. She thinks this is really cool mathematically, and thinks through all the mathematico-physical facts involved.
Here is the question: Does Mary have enough information to know that the Solar System contains conscious life?
If not, physicalism seems to be in trouble.
Alex,
ReplyDeleteYour question gets the obvious answer "yes" from me -- and I am a substance dualist about mind.
When we use our brains to think, we agent-cause them to do things that they would be highly unlikely to do were they not being moved by our souls -- in my opinion -- and there would probably have been systematic changes in the nature of that, during that billion years. Since all of that data would be in the "physical arrangement" bit of your question, I find the obvious answer to your question to be "yes".
But I suspect that many other people, perhaps taking "physical arrangement" (or maybe "physical state of the laws") to mean something else, will think that the obvious answer is "no". For them, your question may well seem to be a good argument against physicalism.
I conclude that your argument is essentially rhetorical, rather than logical.
Alex,
ReplyDeleteI suspect that a physicalist could also say that the obvious answer is "yes" as follows.
That "physical arrangement" data would include all the books written on the subject of consciousness, and every other use of words like "conscious" in every other book, and all the utterances of such words, in every human language, and all the brain states of the speakers and listeners, and so on and so forth. The patterns would presumably show there to have been something called, in English, "conscious life" during that billion years.
This would require Mary to have a good theory of what sort of behavior is emblematic of consciousness. But I don't see how she would gain that based on slight amounts of self-observation. The books would not help unless she recognized them as the products of mind and could translate them, which is dubious.
ReplyDeleteOh, I see now. I now think that your argument is pretty good, logically.
ReplyDelete...although, I am unclear as to why exactly this is a problem for physicalism. Could you spell that out for me?
ReplyDeleteThe way I see it, Mary can know that something in this universe changed over time. Patterns emerged that did not follow from the physics. She will not know that it is consciousness evolving, because she does not know enough about that side of things to identify it as such. But why is that a problem for physicalism?
Well, if physicalism is true, then all of the reality of our universe is physical reality. Thus, someone who knows all the physical facts about our universe knows every fact about our universe. And in particular, she must know that there is consciousness, since that's one of the facts about our universe.
ReplyDeleteI also meant to specify, though forgot to do so, that Mary is solitary. She doesn't observe other people of her kind, either.
I am no expert on physicalism; but would those who know all the physical facts about our universe have to know every fact about our universe, under physicalism? Or would it only follow from physicalism that they would be able to work out all the other facts if they also knew how those other sorts of facts supervened on the physical facts?
ReplyDeleteAlternatively, what if the existence of consciousness was a physical fact? The existence of consciousness in a purely physical universe might indicate that it was. And then Mary would know about it by virtue of knowing all the physical facts.
Alex
ReplyDeleteMary does have enough information to know that the Solar System contains conscious life if physicalism is true and she doesn't have enough information to know that the Solar System contains conscious life if physicalism is not true, so I am not sure what exactly your argument is supposed to show.
Here's what I am thinking: How would Mary have any idea what physical arrangement consciousness consists in? Think about what the physicalist program to solve this problem is likely to look like: We take beings that we have good reason to think are conscious (namely, ourselves and beings sufficiently like us), and then we reverse engineer their functioning, and try to guess which aspects of their functioning make for consciousness. The analogue for Mary would be to study herself. But she doesn't: I stipulated that she doesn't know much biology, and the only self-study she engages in is looking at herself.
ReplyDeleteMary does know all the physical facts about the Solar System. But that doesn't help, as she cannot make a bridge between the concept of consciousness, which is based on her own experience, and the physical arrangement of stuff in the Solar System.
Alex
ReplyDeleteBut why would someone who knows all the physical facts about the Solar System have to guess anything?
If physicalism is true, consciousness is a physical fact about the solar system.
Let's imagine a simplified version. Suppose that one day our scientists find out that whenever in a brain--human or alien--there is an electrical fluctuation at precisely 47.94 Hz, consciousness occurs. But how could Mary ever figure this out from the physical facts? Physical facts will tell her when there is an electrical fluctuation at precisely 47.94 Hz. But how could she possibly know that this is correlated (or identical) with consciousness?
ReplyDeleteThe way *we* would know this is by doing experiments where basically we ask subjects questions, and from their answers we conclude when they are or were conscious, and then we notice that this consciousness correlated with the electrical fluctuations in their brains. Mary could do such experiments on people of her species. But I stipulated that she doesn't: she doesn't know anything about the biology of her species beyond superficial stuff. It is true that the physical description of the solar system would include *our* experiments. But she wouldn't be able to interpret what the subjects of our experiments say unless she knew them to be people and their noises to be language. But how could she know that they are people? Only by comparison between their behavior and hers. But remember that she doesn't know much about her own behavior, and so she doesn't have enough data to know what sorts of behavior are indicative of personhood.
Alex
ReplyDeleteBut in that case it is a physical fact that an electrical fluctuation at precisely 47.94 Hz causes consciousness. And that follows from other physical facts.
If we know all physical facts about our universe as well as the laws governing them, we don't have to do experiments. Consciousness could, in that case, be described in a mathematical way, say "X+3Y²-24Z³* 47.94Hz = C" in which C stands for consciousness. Mary, being a mathematician, of course understands this, hence she knows that there is concious life.
Physical facts are expressed in the language of physics. "Consciousness"is not in the language of physics.
ReplyDeleteAlex
ReplyDelete"Physical facts" is not in the language of physics either.
Right. It is a physical fact that energy is conserved, but it is not a physical fact that it is a physical fact that energy is conserved.
ReplyDeleteAlex
ReplyDeleteHow is that relevant? A physicalist might say that consciousness is a physical fact. He doesn't say that it is a physical fact that consciousness is a physical fact.
No disagreement there.
ReplyDelete