Why and How Does Consciousness Seem the Way It Seems? Daniel C
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Why and How Does Consciousness Seem the Way it Seems? Daniel C. Dennett Are-expression of some of the troublesome features of my oft-caricatured theory of Author consciousness, with new emphases, brings out the strengths of the view and shows how it comports with and anticipates the recent introduction of Bayesian ap- Daniel C. Dennett proaches to cognitive science. daniel.dennett$tufts.edu Keywords #ufts %niversity Bayes | Consciousness | Hume | !nversion | "ualia | #ransduction &edford, &A, %.'.A. Commentator David Ba(ler davidhbassler$gmail.com )ohannes *utenberg-Universit+t &ain,, *ermany -ditors #homas &et,inger met,inger $uni-main,.de )ohannes *utenberg-Universit+t &ain,, *ermany )ennifer &. .indt /ennifer.windt$monash.edu &onash %niversity &elbourne, Australia 1 Introduction People are often baffled by my theory of con- and 2esse Prin/ '()+(,, 3now better, and offer sciousness, which seems to them to be summed theories that share important features with up neatly in the paradoxical claim that con- mine. toyed with the idea of tryin! to re-offer sciousness is an illusion. How could that be? my theory in terms that would signal the areas Whose illusion? And would it not be a con- of agreement and disagreement with these wel- scious illusion? What a hopeless view! n a bet- come allies, but again, life is short, and have ter world, the principle of charity would set in found that tas3 simply too much hard work. 4o and they would realise that probably had with apologies, "m goin! to restate my position somethin! rather less daft in mind, but life is with a few new—or at least newly emphasi/ed short, and we"ll have one less difficult and coun- 5wrin3les, and let them tell us where we agree terintuitive theory to worry about if we just dis- and disagree. miss $ennett"s as the swiftly self-refutin! claim take one of the usefully wron! landmarks that consciousness is an illusion. %ther theor- in current thin3in! about consciousness to be ists, including, notably, Nicholas Humphrey Ned Bloc3"s attempt to distinguish 7phenom- '())*, ()++,, -homas Met/inger '())0, ())1, enal consciousness8 from 7access consciousness.8 Dennett, D. C. 012345. .hy and How Does Consciousness 'eem the .ay it 'eems6 !n #. &et,inger 7 ). &. .indt 0-ds5. Open MIND: 320#5. 8ran9furt am &ain: &!;D *roup. doi: 10.34421<=>?@=4?4>21A4 1 | 33 www.open-mind.net His view has several problems that have poin- cones, to yield spi3e trains in the optic nerve ted out before '$ennett +119, +11:, ()):; <o- ' "m simplifying, of course,. -he arrival of pres- hen = $ennett ()++,, but my criticisms have sure waves at the hair cells in the ear are simil- not been sufficiently persuasive, so am goin! arly transduced into spi3e trains in the auditory to attempt, yet again, to show why we should nerve, heat and pressure are transduced into yet abandon this distinction as scientifically insup- more spi3e trains by subcutaneous receptors, portable and deeply misleading. My attempt and the presence of complex molecules in the should at least help put my alternative view in air we breathe into our noses is transduced by a a better light, where it can be assayed against host of different transducer molecules in the the views of Bloc3 and others. Here is the out- nasal epithelium. -he common medium of spi3e line, couched in terms that will have to be clari- trains in neuronal axons is well understood, but fied and ad#usted as we go alon!> used to be regarded as a bafflin! pu//le> how could spi3e trains that were so ali3e in their 1. -here is no double transduction in the brain. physical properties and patternin! underlie such 'section +, 7phenomenally8 different phenomena as sight, -herefore there is no second medium, the hearing, touch, and smell? 'see $ennett +1@A, medium of consciousness or, as li3e to call for an exposure of the pu//le., t is still ex- this imaginary phenomenon, the MEdium. tremely temptin! to imagine that vision is li3e -herefore, ?ualia, conceived of as states of television, and that those spi3e trains get trans- this imaginary medium, do not exist. duced 7bac3 into sub#ective color and sound8 2. But it seems to us that they do. 'section (, and so forth, but we 3now better, don"t we? We t seems that ?ualia are the source or cause don"t have to stri3e up the little band in the of our #udgments about phenomenal proper- brain to play the music we hear in our minds, ties '7access consciousness8,, but this is and we don"t have to waft molecules through bac3wards. f they existed, they would have the cortex to be the grounds for our savorin! to be the effects of those judgments. the aroma of bacon or strawberries. -here is no 3. -he seemin! alluded to in proposition ( is to second transduction. And if there were, there be explained in terms of Bayesian expecta- would have to be a third transduction, bac3 tions. (section 0, into spi3e trains, to account for our ability to 4. Why do ?ualia seem simple and ineffable? #udge and act on the basis of our sub#ective ex- -his is an effect, a byproduct, an artifact of periences. -here might have been such triple 7access consciousness.8 (section 9, transductions, and then there would have been 5. Whose access? Not a witness in the <artesian a <artesian -heater $eluxe, li3e the wonderful -heater 'because there is no such functional control room in the film Men in Blac3. But bio- place,. 'section :, logy has been thrifty in us> it"s all done through -he access of other people! %ur 7first-per- the medium of spi3e trains in neurons. ' recog- son8 sub#ectivity is shaped by the pressure of ni/e that dualists of various stripes—a genus 7second-persons8—interlocutors—to have thou!ht extinct not so many years ago—will practical access to what is goin! on in our want to di! in their heels right here. will i!- minds. nore their howls for the time being, thin3in! 6. A thou!ht experiment shows how even color that can dispatch them later in the argument ?ualia can be understood as Bayesian pro#ec- when provide an answer to their implied ?ues- tions. tion “What else could it be?8, 4o there is no MEdium into which spi3e 2 There is no double transduction in the trains are transduced. 4pi3e trains are discrim- brain inated, elaborated, processed, reverberated, re- entered, combined, compared, and contrasted5 -he arrival of photons on the retina is trans- but not transduced into anythin! else until duced than3s to rhodopsin in the rods and some of them activate effectors 'neuromuscular Dennett, D. C. 012345. .hy and How Does Consciousness 'eem the .ay it 'eems6 !n #. &et,inger 7 ). &. .indt 0-ds5. Open MIND: 320#5. 8ran9furt am &ain: &!;D *roup. doi: 10.34421<=>?@=4?4>21A4 2 | 33 www.open-mind.net #unctions, hormone releasers, and the li3e, sounds, and aromas are rendered, you are mak- which do the physical work of guidin! the body in! the stone-ager mistake. -his, have come to through life. -he rich and complex interplay believe, is the stone wall separatin! my view between neurons, hundreds of neuromodulators, from wider acceptance. People pay attention to and hormones is now recogni/ed, than3s to the my arguments, and then, confronted with the persuasive work of $amasio and many others, prospect that ?ualia, as traditionally conceived, as a central feature of cognition and not #ust are not needed to explain their sub#ectivity, bodily control, and one can speak of these inter- they #ust dismiss the idea as extravagant. 7%B actions as transduction bac3 and forth between <%FG4H there are ?ualia!8 -his thou!ht ex- different media 'voltage differences and bio- periment is meant to shoc3 them: your confid- chemical accumulations, for instance,—but ence here, am saying, is no better grounded none of these is the imagined MEdium of sub- than the imagined confidence of the stone-agers #ective experience. that there #ust have to be colors and sounds on 4o there #ust is no home in the brain for the $C$ for it to convey colors and sounds to ?ualia as traditionally conceived. My point can the playbac3 machine. A failure of imagination be clarified by a simple comparison between two mistaken for an insight into necessity. 76ut well-understood media: cinema film and digital when I have a tune running through my head, it media. Birst imagine showin! some stone-age has pitch and tempo, and the timbre of the in- hunter-gatherers a movie usin! a portable 4u- struments is there #ust as if were listenin! to a per-A film pro#ector. Amazing, they would live performance!8 Des, and for that to be non- thin3, but when they were then shown the magically the case, there has to be a representa- frames of film up close, they would readily un- tion of the tune that progresses more or less in derstand5 daresay—that this was not magic, real time, and that specifies pitch and timbre, because there were little blobs of color on each but that can all be accomplished without trans- frame. '-he soundtrac3 might still be bafflin!, duction, without further rendering, in the se- but perhaps they would hold the film up to ?uence of states of neural excitation in auditory their ears and decide, eventually, that the cortex. sounds were #ust too faint for them to hear with Vision isn"t television, and audition isn"t their naked ears., -hen show them a film on a radio.