Robert Kermode

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Consciousness for Grown-ups

There's quite a bit of talk in recent years on the internet and on Youtube in particular on the subject of consciousness.

Some people think neuroscience will explain it.

Others think it's excreted somehow by systems on account of their being information processors.

Some think rocks may have it (just a bit of it), others deny this.

Yet others think quantum physics has got something to do with it.

Let's just be blunt: these people are wrong. Not stupidly wrong, to be clear, but they are wrong. They're barking up the wrong tree (or trees).

Consciousness has nothing to do with neuroscience, nothing to do with quantum physics, nothing to do with information theory. It has nothing to do with science.

In this post I will try to explain what I'm pretty sure is the right way to understand consciousness. But there's a catch: the answer is disappointing. Understanding consciousness requires, in part, understanding what we should expect of our understanding, and it may well not be what you think or want it to be.

(This is the 'grown-up' part: accepting that things may not always be the way you want them to be.)

A DIGRESSION ON INTUITIVENESS AND EXPLANATION

What am I driving at, here? A quick digression: It's the end of the 19^th century, and the newly developed theory of electromagnetism predicts that the speed of light is constant, independent of frame of reference. This brings it directly into conflict with the completely intuitive predictions of Newton's physics, which say this cannot be. Physics is in crisis. What to do? Along comes Einstein, who contrives a completely wacky alternative to Newton where those intuitions are just chucked out the window and there is no conflict. Hey presto, problem solved.

Plausibly, this did not feel like a good solution to many, initially. People naturally crave theories which redeem their intuitions, not ones which just magic them away - so, not some preposterous mathematical apparatus which says time all but stops and your mass tends toward becoming infinite as you approach the speed of light. In an important sense, Einstein's solution was not satisfying.

My point is that the solution to the problem of consciousness looks like this. It won't redeem your intuitions. It will not, for example, vindicate David Chalmers when he says that 'Consciousness is a datum' - this is just a misunderstanding. So, it's in a sense disappointing. This being said -and this bit is crucial- what I am offering really is a proper, non-trivial, fully adequate solution.

A closely related point is this. When we think about consciousness, we sometimes imagine there are facts we are missing: are lobsters conscious? Do they feel pain? We really want a theory which will answer that very question, as we conceive its terms (i.e., in terms of qualia). And we're just not going to get it, because its terms are misconceived. It's like puzzling about what the underside of the Earth, conceived as a flat disc, looks like.

Really, then, I have two, separate tasks:

1) To lay out a theory of how our minds work in which the problem of consciousness does not arise, and
2) Separately, independently, to explain how it is that this theory's admitted counter-intuitiveness is not a defect.

I will try here quickly to do, in very general terms, the first of these things. It gets a bit heady in places, but hopefully that's what you signed-up for when you clicked on this blog-entry. The discussion about why this is a good explanation is ...(not yet written).

TWO PICTURES OF OUR SELVES: PRIVATE OR PUBLIC?

Many of us surely are familiar with the 17^th c. philosopher Rene Descartes and his thought experiment, in which he set out systematically to question everything he could and landed at bottom, as the only thing which cannot be doubted, with the fact of his own existence --I think, therefore I am. In the course of this thought experiment he imagined the possibility that all of his experiences (the paper in his hand, the fire in the hearth and so on) were not what they seemed, but were instead the work of an evil demon deceiving him. This line of thought of Descartes' has got a persistent foothold in our culture, even serving, for example, in a modern technological variant, as the premise for the movie, The Matrix.

Descartes painted, in a compelling way, a familiar picture we have of ourselves. The core thought is that we are, as rational thinkers, completely self-sufficient. Other people may be helpful in getting us to a point where we can have the thoughts we do, but they are really just a convenience. Our thoughts are enhanced by all the things we learn from one another, but that's just gravy. Our ability to think rationally is primarily individualistic, and only derivatively social. This, then, is,

Position 1 (Descartes et. al.): "The Private Reflection View" - rationality is inherently solitary.

The alternative, inconsistent picture, pioneered by the 20^th c. philosopher Ludwig Wittgenstein, is that thinking rationally is in the first instance a public activity. The solitary thoughts you have when quietly warming yourself by your baseboard heater or floating in your sensory deprivation tank or wherever, are possible only to the extent that they can in principle at least be expressed in a broader, public linguistic context:

Position 2 (Wittgenstein): "The Public Communication View" - rationality is inherently public.

Our point here is that there are solid reasons to believe Wittgenstein was right (reasons beyond the ones Wittgenstein himself gave), and this has bigger implications than you might think. Contrary to our familiar understanding, thinking rationally must in the first instance be a public activity (the public activity makes possible the private).

"Private thoughts are impossible?! What? That can't be right!"

Yes, this is a natural reaction -it's important to get clear on the sense in which it's meant to be true. And part of the point of all that talk at the outset about intuitions and Einstein was to open the door to questioning this reaction, when it bubbles-up.

THREE QUESTIONS, TO GET TO THE POINT

Now, three questions you might have:

What does this even mean?
Why should I think it's true?
What has it got to do with consciousness?

QUESTION 1: WHAT DOES IT MEAN TO SAY THINKING RATIONALLY IS FUNDAMENTALLY PUBLIC?

Our way into this is through language. Concerning language, here are three obvious thoughts and a further question:

* Thought 1. A main use of language is to serve as the medium for your private reflections (Descartes' activities).

(i) Language is used for thinking

* Thought 2. A second main use of language is to serve as the medium of interpersonal communication.

(ii) Language is used for communicating

* Thought 3. What makes language special -what enables its roles in private thought and in communication- is its 'semantic' properties: the meanings of its words, and the possibility of its sentences' being true.

(iii) Semantic properties --word-meaning and sentence-truth or falsity-- make thinking and communication possible

* Question. Which is most basic? Does language come by its semantic properties in virtue of

being used in private reflection, which then fortuitously makes possible the communication use? Or is it rather that
communication gives rise to the semantic properties, which fortuitously makes possible private reflection? Which comes first?

long footnote: Some people will be thinking, here, yeah, a brain is really just a complicated machine, and evolution has given rise to this encoding mechanism (language) which allows us to transmit state from one such machine to another. The fine details of how exactly this all works remain to be figured-out, but there's no deep mystery. So we don't really have much use for this talk of semantics.
My response: I agree with most of that sentiment. Talk of semantics does not intersect with any of that brain-as-machine understanding. Where I differ is I think we need semantics and related concepts to understand ourselves as agents, which is a completely different kind of understanding than you're talking about. And I think, too, that this understanding of ourselves as agents is not something we can do without. These are big claims, for another day.

I hope it's clear that Descartes was committed to the reflection-first view. Had he believed his words would not have meaning but for the existence of other people, he could hardly have gone about doubting those very people's existence.

For a number of reasons, it's fair to say that like Descartes, effectively all of contemporary thought about semantics subscribes to the reflection-first view. To give you a sense, notice that if you take this view, a question arises as to whether the meanings you've privately assigned the words of English are the same as the ones I have - that what you mean by 'rabbit', for example, is the same as what I do. Now, you might think, well, yeah, but in general that gets sorted-out, obviously, right? There's some kind of calibration and error checking that makes sure we're pretty much always in alignment, right? (And, you might also think, occasionally this kind of mix-up really does happen). Well no, actually. The question as to whether and how you can nail down that we've broadly assigned the same meanings to our words is a central preoccupation of modern thinking about semantics (google 'gavagai'). And my point is, it is generally not recognized that this is a problem only if we take the reflection-first view, that the option is available to treat it as a reductio ad absurdum of it. The view is so baked-in to our thinking that we don't notice it.

There are lots of problems with the reflection-first view, but it is at least a starting-point for theorizing, and it's got a lot going for it intuitively ("You have to have had your own thoughts before you can communicate them, right?" -Possibly not so simple...). Wittgenstein was one of the few to doubt it, but arguably he didn't give us enough in the way of an alternative - didn't give us a sufficiently robust way of understanding the alternative, communication-first view- to challenge the orthodoxy.

Here's the thing about the reflection-first view:

it commits us to a quite specific view of meaning and of our relation to the world. (I'll say more about this in a minute)
this view of meaning and our relation to the world commits us to a way of thinking about consciousness.
this way of thinking is completely intuitive - very hard to unseat - and also deeply problematic.

Here's the thing about the communication-first view:

It gives us a very different way of thinking about meaning and our relation to the world.
It has as a consequence that philosophical consciousness reports are both predictable but ultimately benign nonsense.
It is quite possible to give a robust, clear, theoretically intelligible defence of it.

I don't pretend to be doing that here, in case you're wondering.

So, that was my short answer to the first question, what does it mean to say thinking rationally is fundamentally public? I admit there's lots more to say. We're butting-up against some big questions.

QUESTION 2: WHY SHOULD I THINK IT'S TRUE?

This too is a big topic. I admit, all I can really do here is to point to how the argument works.

As mentioned, we care about the semantics of words (namely, meanings), and of sentences (truth-values).
A basic question for semantics is, What is the relation between these two things, word-meaning and sentence-truth?
It has seemed that the only way to relate them is by treating words as atomic/basic, somehow to equip them with individual meanings, and then to try to set up an apparatus of rules to infer truth-values from the sentences we make with them. The project of doing this is what's called 'compositional semantics'.

The received view is that word-meaning is 'prior to' sentence-truth

There are solid reasons for thinking this project is misguided, reasons not original to me. And there is an alternative, if the case can be made that the compositionalists' goal of providing a systematic set of rules is misguided. The alternative is to take as basic our credibility valuations of sentences, and to build out from them to meanings.

The alternative view is that sentence-truth is prior to word-meaning

The consequence of switching to this view is a much simpler theory, one which - if you are willing to throw out some broken-down theoretical baggage- does everything you should ask of such a theory.

The hitch is that you can only anchor the essential objectivity of truth, on this view, in the interpersonal exchange of sentences. I know that may look a bit flimsy at first glance, but it can be made quite resilient. (and, to be clear, it doesn't mean committing to the "whatever we agree about is true" understanding of truth).

So we have two pictures:

Picture 1 (corresponding to the Private Reflection View):

Reflection prior to communication
Word meaning prior to sentence truth/falsity
Objectivity of language grounded in word-world relations. ⇐ highly problematic

Picture 2 (corresponding to the Public Communication View):

Communication prior to reflection
Sentence truth/falsity prior to word/meaning ⇐ highly counter-intuitive
Objectivity of language grounded in interpersonal exchange.

And my claim, admittedly not really argued here, is that the first, common picture has a ton of problems and the second is surprisingly graceful and simple, once you get it.

So, that was my answer to the second question, why should you think it's true?

QUESTION 3: WHAT DOES THIS HAVE TO DO WITH CONSCIOUSNESS? (Getting to the point, finally)

The thing is —and here's where we get really counter-intuitive and to some, unsatisfying— the usual, reflection-first picture tells us we have a rationally significant, direct relation to things. Meaning is about tying words to those things. Grounding the objectivity of our thoughts and the truth of our sentences, requires there to be this relation. This being accepted, the only way, or certainly the most obvious way, to make sense of consciousness reports is to posit things corresponding to the words we use in making those reports (hence qualia).

The alternate way of thinking about semantics is very different. Meaning is not about word-world relations. Rather, word meanings are distillations from the sentences we accept to be true. Sentence truth is really all there is - meanings do no real explanatory work. Crucially, with this understanding, language can't get outside of itself. That should be kind of an obvious thought for people who ruminate on this stuff regularly, but it's very hard for some people to accept. Only a sentence can justify another sentence.

Accepting this does not dispatch the usual objects we talk about - it does not interfere with common sense, or with science. But it does change how we think about them in our philosophical moments - Descartes', or the Wachowskis' if you prefer.

The case for thinking this theory is true is that it is complete and simple and fully coherent, unlike the alternative. But it is counter-intuitive and, since it makes us dependent on one-another in a way we didn't expect, possibly unwelcome.

The old, reflection-first model of language commits us to a certain view of the way we relate to the things in the world, which includes dogs and avocados and smartphones, not to mention quarks and quantum-electrodynamic fields. And into the mix is our relation to conscious experiences.

When we re-conceive semantics, we keep the dogs and avocados and smartphones and so on because these are all things we can talk publicly about, and public talk is the core of semantics. But philosophers' (and regrettably, increasingly many scientists') 'conscious phenomena', because they are fundamentally personal (private, if you like) are lost.

The key is that the real problem is how, in doing philosophy (and get real: when you're wondering what consciousness is, you're doing philosophy, not science, like it or not), we usually think about our relation to everything: dogs, smartphones, clouds and quarks, yes, and also the way garlic tastes to you and the tickle in your big toe - everything. Conscious experiences as philosophically understood are not special in this regard. They're special only in that when we get things right, their fundamentally private character entails the speciousness of their existence.

Wittgenstein has this analogy in talking about conscious experience. He says that our sensations talk is comparable to what would be the case if we each had a box with a beetle in it we liked to talk about but which only we ourselves could ever see. His thought is that the beetle itself cancels out of the equation, so to speak - it is irrelevant.

Building on Wittgenstein, our slogan might be, the beetle in the box is the world. Or: Il n'y a pas de hors-texte.