Conversations with my coffee maker

Originally published 14 November 1994

I had been read­ing Roger Pen­rose’s new book on the sci­ence of human con­scious­ness and want­ed to dis­cuss it with my wife.

“Not now,” she said, “I’m watch­ing television.”

So I stretched out on the couch and tried to join in. The last thing I remem­ber before drift­ing off to sleep was a com­mer­cial for a Black & Deck­er cof­fee mak­er: “The cof­fee mak­er that’s capa­ble of intel­li­gent thought at 7 a.m.”

I awoke at sev­en, still eager to dis­cuss Pen­rose’s book. My wife was asleep upstairs. I made my way to the kitchen and engaged our cof­fee mak­er in conversation.

“What do you think of Roger Pen­rose’s con­tention that com­put­ers will nev­er become con­scious?” I asked.

“Who is Roger Pen­rose?” the cof­fee mak­er queried, with com­put­er­ly attention.

“He is a pro­fes­sor of math­e­mat­ics at Oxford Uni­ver­si­ty, a physi­cist who has worked with Stephen Hawk­ing on the struc­ture of the uni­verse, a com­put­er whiz, and about as close to an all-round genius as one could hope to find.”

“Is he the guy who wrote the pop­u­lar book The Emper­or’s New Mind a few years back?”

“Yeah, that’s him. The book spent some time on the New York Times best­seller list. Not bad for a rather tech­ni­cal work on com­put­ers, brains, and physics.”

“It seems there’s a lot of inter­est in the prob­lem of con­scious­ness,” said the cof­fee mak­er, “and espe­cial­ly in the ques­tion of whether com­put­ers might some­day achieve human lev­els of self-awareness.”

“Indeed, there is,” I respond­ed. “Almost every few months anoth­er book comes out by a famous sci­en­tist work­ing on the prob­lem of con­scious­ness. For exam­ple, ear­li­er this year Fran­cis Crick, co- dis­cov­er­er of the struc­ture of DNA, pub­lished a book on the sub­ject, called The Aston­ish­ing Hypothesis.

“What is his ‘aston­ish­ing hypothesis’?”

“That con­scious­ness and self-aware­ness will some­day be under­stood pure­ly in neu­ro­bi­o­log­i­cal terms, with­out ref­er­ence to mind-body dual­ism or quan­tum physics. In oth­er words, the brain is a com­put­er, with neu­rons fir­ing away like sil­i­con chips.”

“And Pen­rose, what does he think?”

“Pre­cise­ly the oppo­site. That con­scious­ness and self-aware­ness will for­ev­er elude com­put­ers. There is some­thing about the way our minds work that is non-programmable.”

“Then does Pen­rose believe that sci­ence will nev­er explain the mind?”

“No. Only that today’s physics is insuf­fi­cient to explain con­scious­ness. He looks for­ward to an expla­na­tion that evokes the mys­ter­ies of quan­tum physics…”

“Mys­ter­ies?”

“Well, not mys­ter­ies exact­ly. With com­put­ers, a data bit is either yes or no. In the quan­tum world, a sin­gle elec­tron or pho­ton can be yes and no, at the same time. Two places at once, in a man­ner of speaking.”

“Sounds like a vio­la­tion of com­mon sense.”

“You’re right. That’s why Pen­rose looks to quan­tum physics to explain those aspects of con­scious­ness that would appear to vio­late pure­ly com­pu­ta­tion­al sense. Intu­ition, for exam­ple. Or our sense of free will.”

“How does he get con­scious­ness out of the quan­tum behav­ior of indi­vid­ual elec­trons or photons?”

“That’s the prob­lem. Some­how these almost mag­i­cal quan­tum effects would have to cohere across large areas of the brain. But large- scale quan­tum coher­ence, as we present­ly under­stand it, only occurs at extreme­ly low tem­per­a­tures, near absolute zero. The brain would seem to be too warm for this to happen.”

“You’re los­ing me. Remem­ber it’s only sev­en in the morning.”

“Pen­rose thinks nature may have evolved a way to achieve what tech­nol­o­gists have not yet accom­plished and physi­cists have not yet explained.”

“You mean the brain is a quan­tum device that escapes the rig­or­ous­ly pro­gram­ma­ble restric­tions of com­put­ers? Makes quan­tum leaps, so to speak? Insights? Flash­es of genius?”

“Yeah, some­thing like that.”

“But we don’t yet know enough physics to explain how it happens?”

“Right. Accord­ing to Pen­rose, what’s miss­ing is a the­o­ry con­nect­ing the quan­tum world of indi­vid­ual par­ti­cles to the clas­si­cal world of large-scale activ­i­ty. Crick has a sim­i­lar dif­fi­cul­ty he calls the ‘bind­ing prob­lem,’ explain­ing how the fir­ing of indi­vid­ual neu­rons can coa­lesce to form coher­ent thoughts and perceptions.”

“So, who is right, Pen­rose or Crick? Can com­put­ers become self- aware or not?”

“At this stage, these guys are whistling in the dark. We just don’t know enough about the phys­i­cal basis of con­scious­ness to say who is right. But this kind of spec­u­la­tion cer­tain­ly sug­gests fruit­ful lines of inquiry, and helps inspire pub­lic inter­est that will sup­port research.”

“Sounds like the next decade might be an excit­ing time for brain research. How about a cup­pa coffee?”

“Good idea. I think I hear my wife stir­ring upstairs. It’s been fun talking.”