The problems of consciousness: a taxonomy

David Chalmers has had an enormous impact on how philosophy deals with the mind. He famously coined the distinction between the ‘easy problems’ of consciousness, or how the brain works, and the ‘hard problem’ of consciousness, or why we’re conscious at all.

In reality, lots of the problems Chalmers tags as “easy” are very complex & difficult to answer. But in his defense it’s clear that there is a difference in kind between these problems: eventually, if we follow the templates cognitive science has laid out, with enough time & brainpower & resources we can likely make concrete progress on any given question about how the brain processes information [for a thoughtful & amusing dissent, see here]. But the same doesn’t seem true on the so-called ‘hard problem’ — there seems to be some metaphysical confusion there, some uncertainty as to what kind of answer we’re looking for.

This week, Chalmers posted a new draft about “The Meta-Problem of Consciousness” where he discusses this confusion. Here’s how he sets things up:

The meta-problem of consciousness is (to a first approximation) the problem of explaining why we think that there is a problem of consciousness.

Just as metacognition is cognition about cognition, and a metatheory is a theory about theories, the metaproblem is a problem about a problem. The initial problem is the hard problem of consciousness: why and how do physical processes in the brain give rise to conscious experience? The relevant sort of consciousness here is phenomenal consciousness. A system is phenomenally conscious if there is something it is like to be that system, from the first-person point of view. The meta-problem is roughly the problem of explaining why we think phenomenal consciousness poses a hard problem, or in other terms, the problem of explaining why we think consciousness is hard to explain.

The hard problem of consciousness is one of the most puzzling in all of science and philosophy, and at the present time, there are no solutions that command any sort of consensus. The hard problem contrasts with the easy problems of explaining various behavioral functions such as learning, memory, perceptual integration, and verbal report. The easy problems are easy because we have a standard paradigm for explaining them. To explain a behavioral function, we just need to find an appropriate neural or computational mechanism that performs that function. We know how to do this at least in principle. In practice, the cognitive sciences have been making steady progress on the easy problems.

On this analysis, the hard problem is hard because explaining consciousness requires more than explaining behavioral functions. Even after we have explained all the behavioral functions that we like, there may still remain a further question: why is all this functioning accompanied by conscious experience? When a system is set up to perform those functions, from the objective point of view, why is there something it is like to be the system, from the subjective point of view? Because of this further question, the standard methods in the cognitive sciences have difficulty in gaining purchase on the hard problem

However, there is one behavioral function that has an especially close tie to the hard problem. This behavioral function involves phenomenal reports: the things we say about consciousness (that is, about phenomenal consciousness). In particular, many people make problem reports expressing our sense that consciousness poses a hard problem. I say things like “There is a hard problem of consciousness”, “It is hard to see how consciousness could be physical”, “After explaining behavioral functions, there remains a further question”, and so on. So do many others. It is easy to get ordinary people to express puzzlement about how consciousness could be explained in terms of brain processes, and there is a significant body of psychological data on the “intuitive dualist” judgments of both children and adults.

The meta-problem of consciousness is (to a second approximation) the problem of explaining these problem reports. Problem reports are a fact of human behavior. Because of this, the meta-problem of explaining them is strictly speaking one of the easy problems of consciousness. At least if we accept that all human behavior can be explained in physical and functional terms, then we should accept that problem reports can be explained in physical and functional terms. For example, they might be explained in terms of neural or computational mechanisms that generate the reports.

Although the meta-problem is strictly speaking an easy problem, it is closely tied to the hard problem. We can reasonably hope that a solution to the meta-problem will shed significant light on the hard problem. A particularly strong line holds that a solution to the meta-problem will solve or dissolve the hard problem. A weaker line holds that it will not remove the hard problem, but it will constrain the form of a solution.

… Earlier, I motivated the meta-problem as follows: “if we accept that all human behavior can be explained in physical and functional terms, then we should accept that phenomenal reports can be explained in physical and functional terms.” To a first approximation, then the meta-problem asks for an explanation of problem reports in physical or functional terms. Ideally, we would like to specify neural or computational mechanisms that are responsible for phenomenal reports.

Although the meta-problem is strictly speaking an easy problem, it is closely tied to the hard problem. We can reasonably hope that a solution to the meta-problem will shed significant light on the hard problem. A particularly strong line holds that a solution to the meta-problem will solve or dissolve the hard problem. A weaker line holds that it will not remove the hard problem, but it will constrain the form of a solution.

 

In short, by talking about the ‘meta-problem of consciousness’ Chalmers is offering a way to unify the field of consciousness research. There are lots and lots of different research factions, each with their own idiosyncratic metaphysics of how consciousness works, but absolutely all theorists should be able to discuss the meta-problem: why we think there’s a “hard problem” of consciousness, and what generates the confused utterances we make about it. It’s a clever, ontologically-agnostic way of pointing everyone toward the same goal. To get people in wildly-different echo-chambers talking to each other a little bit more.

This seems like a really good strategy.

That said, I’d like to step back a bit here and propose an alternate framing: the core mystery in all of this is whether there is formal structure to consciousness. An example of something with formal structure is electromagnetism: Faraday and Maxwell were able to unify disparate observations about how electricity and magnetism behave into a formal law– which is to say a mathematical object– that proved highly predictive in novel situations.

On the other hand, an example of something without formal structure is our concept of ‘life’. Are viruses alive? How about cryogenically frozen humans? How about virtual humans on The Sims? These are not questions with crisp answers, because ‘life’ itself doesn’t seem like a metaphysically crisp term. There is no deep structure to be discovered. So the real question here is whether consciousness is inherently crisp (like electromagnetism) or inherently fuzzy (like ‘life’, or ‘justice’, or ‘heavy’).

Importantly, if there is formal structure to consciousness, we should be able to build useful things with this knowledge! Just as a fuller understanding of the structure of electromagnetism led to radio, television, the transistor, and a million more things, we should expect lots of practical, useful inventions to come out of formal consciousness research. (Indeed, the presence of such things will be the best de facto argument that there is formal structure to consciousness.)

In shortI’d offer the following revised taxonomy:

  • The ‘easy problems‘ of consciousness are the technical problems of how the brain processes information;
  • The ‘hard problem‘ of consciousness is the mystery of what sort of thing consciousness is;
  • The ‘meta-problem‘ of consciousness is the mystery of what kind of question the ‘hard problem’ is;
  • The ‘real problem‘ of consciousness is whether consciousness has crisp formal structure, or not;

And finally,

  • The ‘important problem‘ of consciousness is what makes some experiences feel better than others.

This ‘important problem’ of consciousness is QRI’s main focus for two reasons: first, it literally is the important thing for morality, ethics, and the flourishing of humans and sentient beings. Second, it’s plausibly the most tractable place to start. The c. elegans of qualia, the first line in the Rosetta Stone of consciousness. Cracking the important problem should lead to concrete progress on the easy, hard, meta, and real problems.

High-res link.