Against full panpsychism

I have access to two kinds of information about consciousness: I know the occasions on which I am conscious and the occasions on which I am not. Focusing on the second, we get this argument:

1. If panpsychism is true, everything is always conscious.

2. In dreamless sleep, I exist and am not conscious.

3. So, panpsychism is false.

One response is to retreat to a weaker panpsychism on which everything is either conscious or has a conscious part. On the weaker panpsychism, one can say that in dreamless sleep, I have some conscious parts, say particles in my big toe.

But suppose we want to stick to full panpsychism that holds that everything is always conscious. This leaves two options.

First, one could deny that we exist in dreamless sleep. But if we don’t exist in dreamless sleep, then it is not possible to murder someone in dreamless sleep, and yet it obviously is.

Second, one could hold that we are conscious in dreamless sleep but the consciousness is not recorded to memory. This seems a dubious skeptical hypothesis. But let’s think about it a bit more. Presumably, the same applies under general anaesthesia. Now, while I’m far from expert on this, it seems plausible that the brain functioning under general anaesthesia is a proper subset of my present brain functioning. This makes it plausible that my experiences under general anaesthesia are a proper subset of my present wakeful experiences. But none of my present wakeful experiences—high level cognition, sensory experience, etc.—are a plausible candidate for an experience that I might have under general anaesthesia.

Panomnipsychism

We have good empirical ways of determining the presence of a significant amount of gold and we also have good empirical ways of determining the absence of a significant amount of gold.

Not so with consciousness. While I can tell that some chunks of matter exhibit significant consciousness (especially, the chunk that I am made of), to tell that a chunk of matter—say, a rock or a tree—does not exhibit significant consciousness relies very heavily on pre-theoretical intuition.

This makes it very hard to study consciousness scientifically. In science, we want to come up with conditions that help us explain why a phenonenon occurs where it occurs and doesn’t occur where it doesn’t occur. But if we can’t observe where consciousness does not occur, things are apt to get very hard.

Consider panomnipsychism: every chunk of matter exhibits every possible conscious state at every moment of its existence. This explains all our observations of consciousness. And since we don’t observe any absences of consciousness, panomnipsychism is not refutable by observation. Moreover, panomnipsychism is much simpler than any competing theory, since competing theories will have to give nontrivial psychophysical laws that say what conscious states are correlated with what physical states. It’s just that panomnipsychism doesn’t fit with our intuitions that rocks and trees aren’t conscious.

One might object that panomnipsychism incorrectly predicts that I am right now having an experience of hang gliding, and I can tell that I am not having any such experience. Not so! Panomnipsychism does predict that the chunk of matter making me up currently is having an experience of hang-gliding-while-not-writing-a-post, and that this chunk is also having an experience of writing-a-post-while-not-hang-gliding. But these experiences are not unified with each other on panomnipsychism: they are separate strands of conscious experience attached to a single chunk of matter. My observation of writing without gliding is among the predictions of panomnipsychism.

It is tempting to say that panomnipsychism violates Ockham’s razor. Whether it does or does not will depend on whether we understand Ockham’s razor in terms of theoretical complexity or in terms of the number of entities (such as acts of consciousness). If we understand it in terms of theoretical complexity, then as noted panomnipsychism beats its competitors. But if we understand Ockham’s razor in terms of the number of entities, then we should reject Ockham’s razor. For we shouldn’t have a general preference for theories with fewer entities. For instance, the argument that the world will soon come to an end because otherwise there are more human beings in spacetime is surely a bad one.

I think there is nothing wrong with relying on intuition, including our intuitions about the absence of consciousness. But it is interesting to note how much we need to.

Do particles have a self-concept?

Of course not.

But consider this. A negatively charged substance has the power to attract other substances to itslf. Its causal power thus seems to have a centeredness, a de se character. The substance’s power somehow distinguishes between the substance itself and other things.

Put this way, Leibniz's (proto?)panpsychism doesn’t seem that far a departure from a more sedate commitment to causal powers.

Panteleology: A few preliminary notes

Panteleology holds that teleology is ubiquitous. Every substance aims at
some end.

The main objection to panteleology is the same as that to panpsychism: the incredulous stare. I think a part of the puzzlement comes from the thought that things that are neither biological nor artifactual “just do what they do”, and there is no such thing as failure. But this seems to me to be a mistake. Imagine a miracle where a rock fails to fall down, despite being unsupported and in a gravitational field. It seems very natural to say that in that case the rock failed to do what rocks should do! So it may be that away from the biological realm (namely organisms and stuff made by organisms) failure takes a miracle, but the logical possibility of such a miracle makes it not implausible to think that there really is a directedness.

That said, I think the quantum realm provides room for saying that things don’t “just do what they do”. If an electron is in a mixed spin up/down state, it seems right to think about it as having a directedness at a pure spin-up state and a directedness at a pure spin-down state, and only one of these directednesses will succeed.

Panteleology seems to be exactly what we would expect in a world created by God. Everything should glorify God.

Panteleology is also entailed by a panpsychism that follows Leibniz in including the ubiquity of “appetitions” and not just perceptions. And it seems to me that if we think through the kinds of reasons people have for panpsychism, these reasons extend to appetitions—just as a discontinuity in perception is mysterious, a discontinuity in action-driving is mysterious.

Christian panpsychism

I’ve just realized that there is something rather attractive about panpsychism from a Christian point of view. All things God has created are in the image of God. Panpsychism allows them to be in the image of God in a very concrete way: by being minded. There seems to be something fitting about all things having an awareness of reality. And there is Luke 19:40. See also this paper.

That said, I think this falls in the general category of speculative arguments about what God would be expected to create, alongside such arguments as that we would expect God to create a multiverse, or Leibniz’s idea that we would expect a world that is infinitely nested in both the macro and the micro directions. Such arguments need to be extremely tentative.

Motivating panpsychism

There is something attractive about an ontology where all the properties are powers, but it seems objectionable.

First, a power is partly defined by the properties it can produce. But if these in turn are powers, then we have a vicious regress or circularity.

At the same time, mental properties do not seem to be purely powers: they seem to have a categorical qualitative character that is not captured by the power to produce something else.

What is attractive about a pure powers ontology is the conceptual simplicity, and the fact that categorical properties seem really mysterious.

There is, however, a modification we can make to a pure powers ontology that gets us out of the problem. There are two kinds of properties: powers and qualia. The mysteriousness objection does not apply to qualia, because we experience them. On this ontology, powers bottom out in the ability to produce qualia.

For this to avoid implausible anthropocentrism, we need panpsychism—only then will there be enough qualia outside of living things for the powers of fundamental physics to bottom out in. So we have an interesting motivation for panpsychism: it yields an attractive ontology for reasons that have nothing to do with the usual concerns in the philosophy of mind.

It’s worth noting that this ontology is similar to Leibniz’s. Leibniz had two kinds of properties: appetitions and perceptions. The appetitions are (deterministic) powers. Perceptions are similar to qualia, but not quite the same, because (a) perceptions need not be conscious, and (b) perceptions are always representational. Unfortunately, the representational aspect leads to a regress or circularity problem, much as the power powers ontology did, since representationality will define a perception in terms of other appetitions and perceptions.

Panrepresentationalism

Panpsychists, as the term is commonly understood, think everything is conscious. An attractive but underexplored view is that everything nonderivatively represents. This was Leibniz's view, I suspect. One can add to this a reduction of experience to representation, but one does not have to.

A multiple-realizability problem for computational theories of mind

Consider a computational theory of mind overlaid on a reductive physicalist ontology. Here’s I think how the story would have to work. We need a mapping between physical system (PS) and an abstract model of computation (AMC), because on a computational theory of mind, thoughts need to be defined in terms of the functioning of an AMC associated with a PS. But there are infinitely many mappings between PSs and AMCs. If thought is defined by computation and yet if we are to avoid a hyper-panpsychism on which every physical system thinks infinitely many thoughts, we need to heavily restrict the mappings between PSs and AMCs. I know of only one promising strategy of mapping restriction, and that is to require that if we specify the PSs using a truly fundamental language—one whose primitives are “structural” in Sider’s sense—the mapping can be sufficiently briefly described.

If we were dealing with infinite PSs and infinite AMCs, there would be a nice non-arbitrary way to do this: we could require that the mapping description be finite (assuming the language has expressive resources like recursion). But with finite PSs and AMCs, that will still generate hyper-panpsychism, since there will be infintely many finite AMCs that can be assigned to a given PS.

This means that not only we have to restrict the mapping description to a finite description, but to a short finite description. Once we do that, we will specify that a PS x thinks the thoughts that are associated with an AMC y if and only if the mapping between x and y is short. One obvious problem here is the seeming arbitrariness of whatever threshold of shortness we have.

But there is another interesting problem. This approach will violate the multiple realizability intuition that leads many people to computational theories of mind. For imagine a reductive physicalist world w^* which is just like ours at the macroscopic level, and even at the atomic level, but whose microscopic reduction goes a number of extra levels down, with the reductions being quite complex. Thus, although in our world facts about electrons may be fundamental, in w^* these facts are far from fundamental, being reducible to facts about much more fundamental things and reducible in a complex way. Multiple realizability intuitions lead one to think that macroscopic entities in a world like w^* that behave just like humans down to the atomic level could think like we do. But if the reduction from the atomic level to the fundamental level in w^* is sufficiently complicated, then the brain to human-like AMC mapping in w^* will fail to meet the brevity condition, and hence the beings won’t think, or at least not like we do.

The problem is that it is really hard to both avoid hyper-panpsychism and allow for multiple realizability intuitions while staying within the confines of a reductive physicalist computational theory of mind. A dualist, of course, has no such difficulty: a soul can be attached to w^*’s human-like organisms with no more difficulty than it can to our world’s human organisms.

Suppose the computationalist denies that multiple realizability extends to worlds like w^*. Then there is a new and interesting feature of fine-tuning in our world that calls out for explanation: our world’s fundamental level is sufficiently easily mapped to a neural level to allow the neural level to count as engaging in thoughtful computation.

Are monads in space?

It is often said that Leibniz’s monads do not literally occupy positions in space. This seems to me to be a mistake, perhaps a mistake Leibniz himself made. Leibnizian space is constituted by the perceptual relations between monads. But if that’s what space is, then the monads do occupy it, because they stand in the perceptual relations that constitute space. And they occupy it literally. There is no other way to occupy space, if Leibniz is right: this is literal occupation of space.

Perhaps the reason it is said that the monads do not literally occupy positions in space is that an account that reduces position to mental properties seems to be a non-realist account of position. This is a bit strange. Suppose we reduce position to gravitational force and mass (“if objects have masses m₁ and m₂ and a gravitational force F between them, then their distance is nothing but (Gm₁m₂/F)^1/2”). That’s a weird theory, but a realist one. Why, then, should a reduction to mental properties not be a realist one?

Maybe that’s just definitional: a reduction of physical properties to mental ones counts as a non-realism about the physical properties. Still, that’s kind of weird. First, a reduction of mental properties to physical ones doesn’t count as a non-realism about the mental properties. Second, a reduction of some mental properties to other mental properties—say, beliefs to credence assignments—does not count as non-realism about the former. Why, then, is a reduction of physical to mental properties count as a non-realism?

Maybe it is this thought. It seems to be non-realist to reduce some properties to our mental properties, where “our” denotes some small subset of the beings we intuitively think exist. Thus, it seems to be non-realist to reduce aesthetic properties to the desires and beliefs of persons, or to reduce stones to the perceptual properties of animals. But suppose we are panpsychist as Leibniz is, and think there are roughly at least as many beings as we intuitively think there are, and are reducing physical properties to the mental properties of all the beings. Then it’s not clear to me that that is any kind of non-realism.

A probabilistic argument against panexperientialism

Let panexperientialism be the view that all fundamental particles have fundamental experiential or protoexperiential properties.

There is good reason to doubt this. Fundamental particles differ as to whether they have fundamental properties like mass, charge and spin. Thus, we should expect them to differ as to whether they have experiential or protoexperiential properties, and hence we should not expect all fundamental particles to have such properties.

A variant argument. For any subset S of types of fundamental particles, there is S-experientialism, which holds that all and only the fundamental particles from S have the fundamental experiential or protoexperiential properties. Panexperientialism then is S-experientialism where S contains all fundamental particle types. But there are many values of S for which S-experientialism explains our consciousness as well (or as badly) as panexperientialism—for instance, S might be all fermions, or all leptons. So what reason do we have to think that of all these, panexperientialism is true? Well, we might think it's the simplest version. Yes, but the simplicity argument is defeated by the inductive considerations of the previous paragraph.

Panpsychism and quantum mechanics

On the Copenhagen interpretation, observation collapses quantum states. If panpsychism is true, there are constant observations even at the microscopic level. But it seems inconsistent with our empirical data to suppose constant collapse at the microscopic level. So if we are right to accept the Copenhagen interpretation, we should reject panpsychism.

I suppose one could get out of this by saying that only sapient observation collapses things. But that would be weird indeed. It would mean that the conscious states of infants and dogs are utterly different from ours, because while we observe only collapsed states, they would have the dubious privilege of having superposed observational states.

Instead of the Copenhagen interpretation, we might be able to run this argument against panpsychism from the plausible postulate that it is impossible for there to be superposed states of consciousness conjoined with physicalism. For by physicalism, conscious states will be physical states. Plausibly, if panpsychism is true, the conscious states of fundamental particles will vary depending on the state of the particle, or at least the identity of the particle. But then superpositions of microstates will result in superpositions of conscious states, if conscious states are phsycial states. But superpositions of conscious states are impossible, we have supposed.

Who cares? After all, panpsychism is crazy!

Well, it may be crazy, but it could also be that physicalism leads to panpsychism. And if so, then an argument against panpsychism would provide an argument against physicalism.