When we discussed politics you confessed to believing in God. Clearly that's not the case, or you wouldn't be asking such silly questions now would you? What's really the case, are you skeptical toward God, or a strong disbeliever?

When we discussed politics you confessed to believing in God. Clearly that's not the case, or you wouldn't be asking such silly questions now would you? What's really the case, are you skeptical toward God, or a strong disbeliever? — Metaphysician Undercover

To believe in God doesn't necessarily mean I believe in dualism or existence of the soul prior to birth or after death. I think of God similar to Spinoza. I also believe in existence after death, but I recognise that I have no clue what that means - that's a faith based belief.

When you talk about the rare nature-explaining philosopher, do you mean subscribers to the Type-Indentity theory? I'm interested to see what you think of people trying to explain what those mental states are made of physically.

then mind and body cannot interact — quine

That's what the pineal gland is for. Everybody knows that.
:)

I haven't read every comment in the thread, so I hope I'm not repeating anything. After reading quite a few, a number of considerations come to mind.

First, regarding the idea that in order for two things to interact, that they must occupy the same space, consider a "space" in a computer simulation or game and the computer, the code, and the world outside of the sim and how they can interact. You could have a virtual space in the simulation in which there are "local", "physical" interactions according to laws given by the code. A body in that world could be an avatar for some entity that isn't an occupant of that virtual space. And some means of interaction could be provided for in the code that would not be detectable in the game world. We do such things all the time in MMORPGs. It is clearly not the case that the things in the game world cannot interact with things outside of it. A player interacts with that world through input devices, but that input is not detectable from within the game world.

Sure, you might then argue that there really is no game world, that everything involved actually resides in the higher, truly physical world, that all "interaction" inside the virtual world is illusory. But such a situation could also be the case in our physical world. Even body-to-body interactions as we imagine them might not be truly mediated via physical mechanisms through space and time. Their true background and what gives rise to correlations between them might go deeper and might be inaccessible to us, belonging to a deeper world that we can't know directly through this one. I'd say that the whole concept of the physical is rather muddy anyway. We don't really understand "physicality" or even substantiality as well as we tend to think we do. Nor do we understand consciousness. Reducing everything to one or the other and then declaring the problems and mysteries eliminated is foolishness.

How do thing-to-thing interactions in the physical world actually occur? Do they occur? Doesn't such an idea assume that there are multiple truly distinct things interacting? In order for there to be interaction in the strict sense of the word, doesn't this require that multiple things are involved? And doesn't this actually run afoul of what Spinoza argued about the problem with multiple substances? If you conceive of particles as truly separate, independent things, one from another, things each standing on their own, so to speak, having self-existence, you are talking about multiple substances, substance here being used in the traditional metaphysics sense. And multiple substances interacting is usually considered problematic. For one thing, if they are truly independent, why are they the same in so many ways? Why are all electrons basically identical? And why do they occupy the same space? How would truly independent substances have anything in common? And if things are not actually separate, then how can they be said to interact?

It could be that the concept of interaction itself is problematic, as it relies on there being a true multiplicity. Instead, all of reality might involve wholeness.


What are we really talking about anyway with causality? Do we even know?


Also, consider that space at least, if not time also, is possibly emergent and not necessarily fundamental. It seems to me a rather old-fashioned way of seeing things to think of atoms and the void as ultimate fundamentals, and yet most people seem to think in this fashion when thinking about the physical, even though modern physics has given us plenty of reason to raise questions here. For one thing, such a view leaves space, time, and atoms unexplained, as well as the laws that govern them. What is space? Is it just an emptiness or absence of things, or is it substantial? Is it a something itself? Is there a "fabric" of space? What is time? What are atoms? How do they interact? How is it that they have substantiality? How is it that there are multiple things? Why are there many identical things? Why do they have the particular properties they do?

In Einstein's theories, space gains its own degrees of freedom and seems to cease to be the empty void of Democritus that people still seem to imagine. What is it then? If spatial geometry can change, what is it that is changing? And what is it exactly that determines that a certain thing is in a certain place in space? How does that thing "know" where it is? How does the universe "know" where it is and whether it will interact with another thing?

There are all sorts of interesting things to think about. If the only thing in the universe is a single astronaut floating in space, where is he? How fast is he moving? Suppose there is another astronaut in view. Who is moving? There is relative motion. Without the other, velocity is undefined. With two astronauts, information about each is available to the other by way of things like light (maybe the astronauts have flashlights), gravity, and so on. But drop down to the level of a single sub-atomic particle. Until an interaction occurs, aren't its position and momentum undefined? At that level, unlike at the level of a large astronaut, where many, many interactions are involved in seeing another astronaut, interactions are comparatively rare. As a single tiny particle, you can't "see" the world around you. You aren't big enough be struck by enough photons or whatever in order to gain information about your surroundings. Prior to an interaction, it would seem, you are effectively isolated, and so your position, momentum, and so on, are undefined. Only upon interaction does any of this become defined. And since things are quantized and discrete, interactions are seemingly on and off. If light were continuous, particles could maybe be thought to receive tiny quantities of light from all around, from many, many objects, and thus not be so blind. The discreteness and quantization gives a different picture. But if you need interaction to gain definite position and momentum, how is it determined whether the interaction happens or not? If it isn't "known" where the particles are, how is it "known" if they collide? Seemingly, interaction is needed to generate information about relative states, but information about relative states is needed to decide if interaction occurs. What is it that keeps track of their respective positions and momenta, if anything? A real position in a real space? What does that mean? Is that compatible with the uncertainties of QM? In a computer simulation of particles, we keep track in the computer's memory. The computer "knows" and compares the positions. What about in the physical world?

How is any of this relevant to the discussion? I think there are questions that few ask about how any sort of interaction occurs. An interaction between two particles in space might require a third unknown factor, one transcending space. And if such other factors could be involved, why couldn't they possibly mediate mind-matter interactions? We just don't know enough to rule such things out. We don't know what mind really is. We don't know what matter/energy really is. We don't know what space is. We don't know what interaction really is. We don't understand causation. So deciding what is possible by means of arguments such as the one presented in the OP is more than a little misguided, it seems to me.


Recently, there has been some stir in the physics world over ER=EPR, and some are beginning to think, in possible glimmers of a theory of quantum gravity, that space itself is emergent and is "stitched together" by entanglement, and represents a sort of network of particles (not particles in the intuitive "tiny rock" sense). But if space is emergent in this sense, where do the particles that, by their entanglement structure, give rise to it, themselves reside? Another space? Why is that needed?

Where, for that matter, is the universe located? Does it have location?

Consider a computer program in which you define a bunch of nodes with "links". Create rules such that information can be moved from node to node, but only across links. Information can be passed at a rate of only one link per time step. Suppose you have nodes linked in a series such as A-B-C-D-E.... Information can go from A to B to C, but never A directly to C, since no such link exists. What happens here is that a sort of space emerges, a one-dimensional space. But in reality, A, B, C, D, E, and so on, are not actually spatially located. They are distinguished logically or informationally only. Spatial "proximity" here takes on a new meaning, having to do with the arbitrary structure of the network. The nodes themselves actually have no location in any true space.

Our space could be analogous to this in that there might not be any true, ultimate space in which particles reside. Reality might be more fundamentally logical/informational.

In our computer program, we could create more emergent spatial dimensions by linking nodes in more ways. We could have A1 linked to both B1 and to A2, for example, giving something like rows and columns. You could then have a 2D "space" "inside" the network, in which such games as Conway's Game of Life could happen. If you are an inhabitant of such a world, it might appear that all causal interaction is truly happening at the level of the things inside that space, between things locally acting on one another, one cell literally touching and thereby influencing its neighbor. In reality, what is responsible for that apparent interaction is something altogether inaccessible to the contents of the game world. It has more to do with the computer running the program and storing information in variables, executing conditionals, comparing variables, and so on. Similarly, in our world, many things might be completely hidden from us. Many of the conditions for the possibility of what we see happening might be based in something happening in a realm transcending the one we have access to.

Remember that correlation doesn't demonstrate causation. What might at first appear to be A causing B might in fact be C causing both A and B. Every time the mercury in the thermometer rises beyond a certain point, I also start sweating, but it would be a mistake to conclude that the rising mercury is causing me to sweat. And realize that when we think we observe physical causation, all we are really seeing is correlation. Every time X occurs, Y occurs. We are seeing patterns in our experience. We don't have any deep justification for our belief that one billiard ball striking another is fundamentally and finally what causes it to move.


Consider being stuck in a dream you can't wake from and trying, from that vantage point, to address certain factors that affect the dream world, such as your physical body. You cannot find that which governs the contents of the dream inside the dream. You can't find, strictly within the dream world, the brain that dreams it. You could not, for example, excise your brain tumor through the dream world. Similarly, in an MMORPG, you cannot find the player of the game inside the game world. You cannot find the computer on which the game is running inside the game world. You cannot find the code inside the game world.

Suppose we create a simulation in which we have a physics that works at the particle level and we evolve a complex world there built of these virtual particles. Now imagine that a scientist composed of such particles studies that world experimentally and adheres to the idea that reality consists only in what can be experimentally verified. Could that scientist, by means of his experiments, ever gain access to the computer on which his world is running? Could he discover the programmers? He might manage to discover laws, and thus, to some small extent, something of the code behind the simulation, but that's about all. So if he were to define reality as being limited to that which is composed of the particles in his world and their interactions, and that which is verifiable by experiments performed on these particles, he would be making a mistake, wouldn't he? He'd be rather short-sighted, but understandably so.


Also, what relevance might Kant have in this discussion? In his view, aren't space and time categories of the understanding? How does this affect the question of interaction between mind and body?


I think it even possible that the physical world is something that happens emergently inside mind, or is in some sense the content of mind, or represents the structure, seen at a certain level, of a kind of mental activity. After all, physics seems to reduce to math and information and maybe ultimately logic, which are themselves decidedly not very "stuff-like", seemingly rather more like cognition. We still, because of physics history, call the small constituents of reality "particles", but when you really examine the concept, the particles of modern physics are not at all what we intuit when using that word. A picture often presented in physics is that of a photon, a discreet packet of energy, being absorbed by an electron and thereby converted into a higher energy state of that electron. What is really happening here? Do we really understand matter-energy equivalence? Consider that a particle itself can be converted into momentum. What is this "stuff" then?

And from the perspective of the photon, because of length contraction, there is no distance or time interval in the crossing. The source and destination electrons are, for the photon, co-located or touching. Perhaps photons aren't real particles moving through space. Maybe space itself isn't what we imagine it to be. A seeming travel of a photon, which has never been observed by the way, might be one electron directly exchanging information with another by a sort of "local" action, transferring energy from one to another.

As little as we currently understand about the deep nature of things, I'd say it is extremely premature to claim that we know that things located in space and things not located in space cannot be related. Also, the idea that there can be nothing real that isn't located in space is absurd, space itself being the perfect example. Is space located in space? No? Is it therefore unreal? The laws of physics, mathematics, and logic are all real and not spatially located.

If space is emergent, as it seems it might well be, then even the things seemingly in space aren't truly located in space. And this would cause trouble for the idea of a problem with interaction between spatially located things and things not spatially located. Instead, we'd be talking about relationships where none of the things involved have true spatial location.

And what if space emerges in mind? What if matter and space are contents of mind? Mind is then clearly not in space and yet it is easy to see that mind could be said to have some bearing on its contents. If you have trouble with this in the big, real world, consider how the argument in the OP would play in a dream. The "dream-physical", or the content of the dream world, lives in the dream world, while the mind transcends it, and yet they clearly are related. But of course, this is not truly a dualistic picture. But a kind of dualism could certainly be apparent or emergent at a certain level.

Where are numbers?