(For Part 15b, see here. and for previous posts see Freewill vrs Determinism Catergory in Left hand sidebar)
Why is it that so much nonsense is written on the subject of consciousness?
(Not here of course, you only get the good stuff here ;-)
How is it for example that one of the top thinkers in the field, Daniel Dennett, can say:
`We're all zombies. Nobody is conscious' (Dennett 1991, p. 406)
And how is it that Christof Koch, a very clever man, and a leading researcher into the neuroscience of consciousness, can make such a fundamental error as to suggest that the proof of consciousness is to be able to identify something odd about a photograph? (previous post)
Here's my answer in a nutshell:
1) From a reductive point of view (see below) there is simply no room for consciousness in the world, therefore
2)it shouldn't exist, but
3)I know it exists because I'm experiencing it now, therefore
4) there is something very odd going on.
5) Most scientists and philosophers can't handle the idea that there's something odd about the world
6) therefore they work very hard to fit consciousness into whatever their world view is, but because it won't fit in...
7) ...they end up defending bizarre statements such as Dennett's "nobody is conscious."
I counted over 200 distinct positions on the subject of consciousness, ranging from Eliminativism (nothing is conscious) to Panpsychism (everything is conscious) then I gave up because there are lots more.
None of these positions can be proved wrong and yet all of them are mutually exclusive. How can this be?
Answering this question takes us to the heart of the issue.
When I was in church at the age of 11 the vicar told us that God invented rainbows as a sign to remind Noah that he would never again destroy the world with a flood. (Actually, in Genesis, God says he invents the rainbow not so that Noah would remember God's promise, but to remind himself, God, of what he has promised: "When the bow is in the clouds, I will see it and remember the everlasting covenant between God and every living creature of all flesh that is on the earth." Gen 9:16. When I see this being seriously discussed on websites such as this one here I find myself fighting the urge to self-mutilate...)
Now, even as an 11 year old I knew there was something very wrong with this. I knew, as every schoolchild does, that rainbows are caused by sunlight reflecting off raindrops. If you have sunlight and rain and the existing laws of nature and observers in the right place you will have rainbows. There is no imaginable world which has sun, rain and observers in which rainbows don't exist. In the language of philosophy, rainbows logically supervene. Not only does God not have to do any extra work to create rainbows, even he can't imagine a world where the prerequisites for rainbows exist but where rainbows don't actually exist. The best he could do, I suppose, is to put in place some kind of illusion so that people don't notice them.
Ah how I wish I'd had the knowledge and confidence to tell the vicar "Given the logical supervience of rainbows I am reluctantly forced to conclude that either God is very easily confused on the matter or that Genesis is not a true and accurate representation of God's opinion on rainbows."
Anyway, back to consciousness. Here's the big question:
Does consciousness logically supervene on the physical facts of the world?
I say no.
How do I justify this?
Well, to test if something logically supervenes on given facts, you simply imagine a world where all the other relevant facts are in place. Then you imagine if such a world must contain that thing.
As we've seen, all alternative worlds with the same physical facts as this rainbow world must contain rainbows, therefore rainbows are an example of supervenience. We can't even imagine a world where this would not be so.
What else in our world does not logically supervene on the facts?
Not much. One thing that doesn't logically supervene on the facts is the laws of the universe. We can imagine a world or alternative universe where the laws of physics are complelely different. It does not mean that such a world or universe exists of course, but we can imagine it, and God could easily make it. Actually, thinking about it, the currently popular theory of the Multiverse does encompass this idea already, so maybe it's not so "out there" after all. I think M-theory also allows for this. Anyway, the important thing to establish logical supervenience is not whether such a thing exists or not but whether or not it must always exist in every case.
Can we imagine a world where everything looks the same as it does now but there is no consciousness apart from our own? Yes we can. In fact, how do you know you are not living in that world already? And if this is the case, consciousness and rainbows belong to fundamentally different categories. Rainbows supervene on the facts, consciousness does not. We'll be exploring this idea in Part d, but just to be clear; I won't be suggesting that you do actually live in a world of unconscious beings, just that the fact you don't know whether you do or not has serious implications for the concept of consciousness.
Before we tackle this idea in more detail, let's look at the idea of Levels of Explanation. Ironically, it was David who first introduced me to the concept when we were at school er 33 years ago.
Take my car. You can describe it in high level terms as a Ford Fiesta FX, or a mode of transport, or a nice little run-around that my parents kindly gave me 4 years ago.
You could also descibe it on a lower level of meaning, for example you could describe it mechanically; prop shafts and spark plugs and wing nuts etc.
You could go lower and describe it through its material construction; metal, plastic rubber etc.
Or you could reduce your explanation of my car to a molecular level; my car is "10 to the whatever" atomic particles.
All these descriptions would be true and each level logically supervenes on higher levels. My car IS both a piece of metal and plastic AND a mode of transport. If you arrange "10 to the whatever" molecules in exactly the same position as my car, you will have a Ford Fiesta LX.
We can choose whichever level of explanation is useful to us at the time. A mechanic will talk in mechanical terms and a chemist will talk in terms of chemistry etc. And neither of them will have any problem with the other.
Now have a go with this sentence: "My love for you is a neural patten firing at 40hz."
If you are very uneasy about this sentence, welcome to the club. You are uneasy because you feel that subjective experience is not merely a higher level explanation of brain activity but is something distinct from it. The objective description does not encompass the subjective experience. They are not higher and lower levels of description of the same thing, they are different things.
The experience of green comes from neurons but is NOT neurons. It is an extra phenomena requiring explanation. The problem is that a physical explanation is causally closed. We can describe everything without the need to bring consciousness into it at all. This is what I mean when I say there is no room for consciousness in the world and this is why we can explain everything about neurons but stil leave the phenomenological experience of green untouched. "My car is molecules" is a different kind of statement to "my sadness is molecules."
Which brings us back to Francis Crick:
"You, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behaviour of a vast assembly of nerve cells and their associated molecules. Who you are is nothing but a pack of neurons."
This is the reductive materialist argument, the idea that all all processes and realities observed in the universe can be explained by reducing them down to their most basic scientific components. Crick is saying that because explanations of joy and sorrow can be reduced to the level of neurons there is nothing MORE to be said about joy and sorrow.
His error surely is in the phrase "nothing but" neurons. Why not reduce it even further and say a person is nothing but a pack of molecules? A person is made of molecules but to say that a person is nothing but a pack of molecules is the kind of thing only a clever philosopher would be stupid enough to say.
The Battle of Waterloo involved a lot of molecules moving about but to say the Battle of Waterloo was nothing but a pack of molecules moving about, is clearly nonsensical.
What can the materialist do about consciousness? They can say it doesn't exist at all, or they can say it is just some epiphenomenon, an ugly "bolted on" thing which has no effect on the world itself but just arises for no apparent reason and is irrelevant to the workings of the world.
And why does it feel something like this to be me? And why does it feel this way and not that way? And why does a neural pattern create this experience of green and not that? And - most importantly - why does it feel like anything to be me rather than nothing at all?
These are things the materialist must remain silent on, or they must take up the position which D J Chalmers calls Don't-have-a-clue materialism:
"I don't have a clue about consciousness...but it must be physical, as materialism must be true."
David suggested recently that we only need philosophy until science comes along to tell us the answers
( "philosophy is what you do until science comes along. Good news: science is here, you can stop philosophizing now.;-)
I suggest that science is just as rooted in philosophy as in any other area of life, and that the conviction that materialism will provide all the answers at some unspecified time in the future is an unjustifiable claim, and that in any case, the claim is a philosophical one rather than a scientific one.
Where does all this take us? It takes us to Zombie Protozoa, coming soon!