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TEDx Talks
Published: 2013-05-24
Source: https://www.youtube.com/watch?v=j_OPQgPIdKg
I'm going to talk about consciousness F. Y. consciousness well it's a freak curiously neglected subject a both in our scientific and our philosophical culture a wise as curious well it is the most important aspect of our lives for a very simple logical reason namely it's a necessary condition on anything being important in our lives that were conscious you care about science philosophy music art whatever you
it's no good if you're a zombie or in a calm right so consciousness is number one all right now we've got a that's the first reason bertambah conserve the second reason is that when people do get interested in that because I think they should they tend to say the most appalling things and I've not been attempted conceal from you some of the most appalling things have
been said about consciousness and then even when they're not saying appalling things they're really trying to do serious research well it's been slow progress has been slow art let me tell you a little bit about some of the difficulties my first got Anderson this I thought well if it's a straightforward Rodman and biology let's get these brain staffers to get busy a figure out how it
works membrane someone already UCS and I talked all heavy duty neurobiologist there and they showed some impatience as they'll as scientists often do when when you ask embarrassing questions but the thing that struck me as one guy said in exasperation very famous nor about just he said look in my discipline it's okay to be understood consciousness but get tenure first yeah tenure first out now I
think I've been working on this for a long time I think now you might actually get tenure by working on consciousness if so that's a real step forward okay now why then is this curious reluctance and here is hostility to consciousness well I think it's a combination of two features of our intellectual culture that like to think they're opposing each other but in fact they share
a common set of assumptions consciousness is not a part of the physical world it's a part of the spiritual world it belongs to the soul and the soul is not a part of the physical world that's the tradition of god the soul and immortality there's another tradition that thinks it's opposed to this but accepts the worst assumption that tradition thinks that we are heavy duty scientific
materialist consciousness is not a part of the physical world either it doesn't exist at all or something else a computer programmer some some damn fool thing but in any case it's not part of science and I used to get an argument that really gave me a stomachache here sought went science is objectivity consciousness is subjective therefore there cannot be a science of consciousness now I love
that argument because it's got a wonderful fallacy of ambiguity over the concept of objectivity and I I've already used up too much time distant just of clearing my breath so to speak but I I want to get to that okay so that's that at these twin traditions are are are paralyzing us out it's very hard to get out of these twin traditions and I have only
one real message in this lecture and that is consciousness is a biological phenomenon like photosynthesis digestion mitosis you and you know in all the biological phenomena and once you accept that most are not all of the hard problems about consciousness simply evaporate and I'm gonna go through some of them okay now I promise you to tell you some of the outrageous things said about consciousness are
not just a because a shortage of time I'm only going to mention four of the worst one consciousness does not exist %HESITATION it's an illusion like sunsets I science has shown are a sunsets I I am and of rainbows are illusions so consciousness is an illusion true out well maybe it exists but it's really something else it's a computer program running enough brains our three no
the only thing exists is really behavior it's embarrassing how influential behaviorism what's but off get back to that and for maybe consciousness exists but it can't make any difference to the world how could spirituality move anything however if somebody tells me that I think you want to see spirituality move something watch I decided consciously to raise my arm and the damn thing goes off Furthermore notice
this we do not say well it's a bit like the weather in Geneva some days it goes off and some days it don't go off now it goes up whenever I damn well wanted to okay I'm gonna tell you how that's possible now I've I've haven't yet given you a definition you can't do this if you don't give a definition people always say consciousness very hard
to define I think is rather easy to the fine if you're not trying to give a scientific definition were not ready for scientific definition but here's a common sense definition consciousness consists of all those states of feeling or sentience or awareness it begins in the morning when you wake up from a dreamless sleep and it goes on all day to you fall asleep or die or
otherwise become unconscious dreams are a form of consciousness on this definition now that's the common sense definition that's our target if you're not talking about that you're not talking about consciousness but they think well I think that's it that's an awful problem how can such a thing exist as part of the real world and this I if you've ever had a philosophy course this is known
as the famous mind body problem I think that has a simple solution to I'm gonna give it to you and here it is all of our conscious states without exception are caused by lower level neuro biological processes in the brain and they are realized in the brain as higher level or system features it's it's about as mysterious as the liquidity of water right the liquidity is
not an extra juice squirted out by the H. two O. molecules it's a condition that the system is in and just as though I as the jar full of water can go from liquid to solid depending on the behavior the molecules so your brain can go from a state of being conscious to a state of being unconscious depending on the behavior of the molecules that famous
mind body problem is that simple alright but now we get into some harder questions outlets I specify the exact features of consciousness so that we can then answer those for objections that I made to it well the first feature is it's really off hand irreducible can't get rid of it you see the distinction between reality and illusion is the distinction between how things consciously seem to
us and how they really are it consciously seems like there's a I like the French Archos hill it seems like there's an arch in the sky or it seems like the sun is setting over the mountains I consciously seems to us but that's not really happening but for that distinction between how things consciously semen how they really are you can't make that distinction for the eggs
very existence of consciousness because where the very existence of consciousness is concerned if it consciously seems to you that you are conscious you are conscious I mean if a bunch of experts come to me and say we are heavy duty neurobiologist and we've done a study of you sorrow and we're convinced you are not conscious you are very cleverly constructed robot I I don't think well
maybe these guys are right you know I don't think that for a moment because I mean I it day card may have made a lot of mistakes but he was right about this you cannot doubt the existence of your own consciousness okay that's the first feature of consciousness it's real and irreducible you cannot get rid of it by showing that it's an illusion in a way
that you can with other standard illusions okay the second feature is this one that has been such a source of trouble to us and that is all of our conscious states have this qualitative character to them there's something that it feels like to drink beer which is not what feels like to do your income tax or listen to music and this qualitative feel automatically generates a
third feature namely conscious states are by definition subjective in the sense that they only exist as experienced by some human or animal subjects some self their experiences some maybe we'll be able to build a conscious machine since we don't know how our brains to it we're not in a position so far to build a conscious machine okay another feature of consciousness is that it comes and
unified conscious feels so I don't just have a side of the people in front of me and the sound of my voice in the way of my %HESITATION shoes against the floor but they occurred to me as part of one single great conscious field the stretches forward and backward that is the key to understanding the enormous power of consciousness and we have not been able to
do that in a robot that did the disappointment of robotics derives the fact that we don't know how to make a conscious robot so we don't have a machine that can do this kind of thing okay the next feature of consciousness after this marvelous unified conscious field is that it functions causally in our behavior I gave you a scientific demonstration by raising my hand but how
is that possible how can it be that this thought in my brain can move material objects well I'll tell you the answer we know I mean we don't know the detail answer but we know are the basic part of the answer and that is or sequence of neurons firing so and they terminate where the a subtle Colina secreted at the axon in place of the motor
neurons argues philosophical terminology here but but when it's secreted the axe on in place of the motor neurons a whole lot of wonderful things happen in the ion channels and the damned harm does now this like think of what I told you one and the same event my conscious decision to raise my arm has a level of description where it has all of these touchy feely
spiritual qualities it's a thought in my brain but at the same time it's busy secreting a subtle calling and doing all sorts of other things as it gets was it makes its way for the motor cortex how a down through the eye through the nerve fibers in the arm now what that tells us is that our traditional vocabularies for discussing these issues I totally obsolete one
and the same event has a level of description words neurobiological and another level of description where it's mental and that's a single event and that's how nature works that's how it's possible for consciousness at a function causally okay now with that in mind with I I. going through these various features of conscience let's go back and answer some of those early objections well the first one
I I said was conscience doesn't exist it's an illusion well I've already answered that I don't think we need to worry about that but the second one had an incredible I influence and may still be around and that is well if consciousness exists it's really something else it's really a digital computer program running in your brain and that's what we need to do to create consciousness
is get that right program you forget about the hardware any hardware will do provided is rich enough and stable enough to carry the program now we know that that's wrong I mean anybody who's a thought about computers at all conceded that's wrong because computation is defined as symbol manipulation usually thought of zeros and ones but any symbols will do you get an algorithm I add that
you can I program in in a binary code and that's what that's the defining trait of the computer program but we know that the that's purely syntactical but that's symbolic we know that actual human consciousness has something more than that it's got a cot a content in addition to the syntax it's got a semantics now that I'm I'm I made that argument thirty well my god
don't think about more than thirty years ago but there is a deeper argument implicit in what I've told you I want to tell you that argument briefly and that is consciousness creates an observer independent reality it creates a reality of money property government marriage I a CERN for conferences I at cocktail parties and summer vacations and all of those are creations of consciousness their existence is
observer relative it's only relative to conscious agents that a piece of paper is money or the bunch of buildings as a university now ask yourself about computation is that absolute like force and massive gravitational attraction or is it observer relative well some computations are intrinsic I add two plus two to get four that's going on no matter what anybody thinks but when I haul out my
pocket calculator and do the calculation the only intrinsic phenomenon is the electronic circuits and its behavior that's the only absolute phenomena all arrests is interpreted by us computation is only exists relative to consciousness either conscious agent is carrying out the computation or he's got a piece of machinery that admits of a computational interpretation now that doesn't mean computations arbitrary I spent a lot of money on
this hard hardware but we have this persistent confusion between objectivity and subjectivity is has features of reality and objectivity and subjectivity has features of claims and them the bottom line of this part of my talk is this you can have a completely objective science are a science where you make objectively true claims about a domain whose existence is subject whose existence is I am in the
human brain consisting of subjective states of sentience or feeling or awareness so the objection that you can't have an objective science of consciousness because it's subjective and sciences object if that's a pun that's a bad pun on objectivity and subjectivity you can have you can make objective claims about a domain that is subjective in its mode of existence and the that's what nor Norrell about that's
what neurologists do I mean if you have patients actually suffer pains and you try to get an objective science of that okay I promised to refute all these guys and I don't have an awful lot of time let but let me refute a couple more them I said that behaviorism ought to be one of the great embarrassment of our intellectual culture are because it's refuted the
moment you think about it are your your mental states are identical with your behavior well think about the distinction between feeling a pain and engaging in pain behavior I will demonstrate pain behavior but I can tell you I'm not having any pains right now so it's an obvious our mistake why did they make the mistake the mistake was and you go back and read the literature
on this you can see this over and over I they think if you accept the is the irreducible existence of consciousness you're giving up on some you're giving up on three hundred years of human progress and human hope and all the rest of it and that the message I want to leave you with is consciousness has to become accepted as a genuine biological phenomena as much
