We are zombies?
Marc, R and I had a strange philosophical discussion this week end, when perhaps we could have spent time in more practical but rewarding things.
R and I have for long been what may be termed bhUta chaitanya vAdins in the old Hindu parlance. We essentially believed that consciousness arose from the neural material. Marc though somewhat closer to electron orbitals than either of us in his daily existence made a strange statement: I seem to accept the reality of consciousness much more than you two, despite you all being born Hindus. We hastily clarified that we do not deny the existence of consciousness like most other Hindus, we merely believe that it has a neural origin. There is a certain philosopher, if we can call him that, named Dan Dennett, who almost argues that there is no such thing as consciousness. Unlike him we do not deny it but realize that it exists. So we decided to make sure that we meant the same thing as Marc in the term “consciousness”.
We agreed that consciousness is the “first person experience”- that is when I see a saffron flag, I have an experience of saffron. Now this is to be distinguished from the basic underlying neurobiological processes: 1) Light from the saffron cloth impinges on my retina. 2) Some retinals buried in the 7-TM cylinders formed by rhodopsin molecules flip. 3) The 7TM protein undergoes a conformational change. 4) This change activates a hetero-trimeric G-protein. 5) The G-protein signal cascade ultimately results in a cascade via an ion channel. 6) This channel opening transmits a neural impulse that ultimately propagates with the intermediaries of synapses and neurotransmitters to the brain…… 7) There the signal is compared with some internal RGB or CMYK color grid and recorded as a color. Some such sequence of steps are involved in color reception and recognition. We are certainly interested in knowing all about the every protein involved in this process and this is the biology if signal recognition. Dan Dennett claims that this is consciousness! We admit that this is not really consciousness, this a functional description of signal reception and recognition process; it is the first person experience of saffron that constitutes consciousness.
So what is explanation that first person experience? I being a philosopher of a certain kind (and also R being influenced by my philosophical trends, before she started to orbit Marc) argued, that it is indeed something hard and we are not in a position to explain first person experience in an easy way. But we clearly see a selective advantage for it and hence believe has been fixed by natural selection. Hence, it has to have a neural origin. Marc retorted that a system without the presence for first person experience by all the requisite signal reception/recognition apparatus that generates should be enough to provide the necessary stuff for the action of natural selection. Thus, he said we could be philosophical Zombies lacking the first person experience but still function efficiently if the functional apparatus were working (as David Chlamers, another philosopher, cogently posited). So indeed the functional apparatus is a product of natural selection, but the first person experience is not necessiated by it. To put in another way the bio-machine can whirr and chug, as seen by the third person biologist, but why does that produce a first person experience.
Marc in a very Chalmersian way believed in the existance of a extra-physical consciousness, that is somehow direct property of existence like mass-energy or charge: that is he feels it to be an axiom in a theory that cannot be explained on the basis of pre-existing axioms like mass-energy, charge or spin. At that point we realized we were reliving the discussions of the great sAmkhyan seers of yore. Many thoughts were flowing and we all felt the need to meditate upon them.