By Zan Boag

American philosopher of mind Daniel C. Dennett’s early years read like something straight out of an adventure book. The son of an academic and an English teacher, he grew up in Winchester Massachusetts, where his grandfather was the town doctor. As WWII erupted, Dennett’s father’s knowledge of the Middle East landed him a role as a spy in Beirut, where he stayed on working after the war ended. It was in Beirut that Dennett spent his early childhood, until his father’s plane was shot down while on a mission in Ethiopia. “So my mother and two sisters and I moved from Beirut to Winchester, where I grew up in the shadow of everybody’s memories of a quite legendary father,” he writes in his autobiography.

Back in Winchester, Dennett was fortunate enough to attend Phillips Exeter Academy, which he says was “a wonderfully intense intellectual stew” where the captain of the football team played second fiddle to the editor of the literary magazine and students read widely and discussed earnestly. This is where Dennett started to shape his thinking, which ultimately led to a PhD at Oxford and a lifelong search for the secret of consciousness – something Dennett claims is not a trick, but rather “a bag of tricks”.

“One of the deepest and most penetrating of errors about consciousness is the idea that it is something that divides the universe in two, that there are the things that have it and the things that don’t and it’s this utterly amazing, nearly magical property,” says Dennett. “They’re wondering about whether some almost impossible-to-define extra-phenomenon, some interior glow or something is going on...and I think they’re just wrong.”

Dennett believes that there’s every degree of sensitivity and reactivity right down to bacteria. “This idea that there’s this salient marvellous property that you either have or you don’t, that’s the mistake. Bacteria are remarkably adroit, sensitive and self-protective and every cell in our bodies is like a bacterium in this way.” He says that if people knew more about what single celled organisms can do they would realise that they are all conscious.

“What do you think consciousness is? As we build up in complexity from bacteria through to starfish to birds and mammals and us it seems to me the most important threshold is actually us, that we have the bigger and more impressive bag of tricks than any other species. But that doesn’t mean that we have this utterly different phenomenon that happens in our heads and it doesn’t happen in any other heads.”

Our bag may be bigger and more impressive, but Dennett doesn’t think that many take advantage of the “tricks” at their disposal. “Most people go through life without any taste for careful analytical thought. They’re excited by whatever they’re excited by,   and so most topics don’t hold their attention. Careful sceptical scrutiny is undertaken by a minority,” he says.

However this situation is no accident – Dennett points out that a fight has been going on for people’s minds for some time: “I think this is something like an arms race that has been going on for thousands of years. The world’s literature is full of stories of innocent young folk being hoodwinked by sharp-talking, clever con-artists. This has been going on in the media and the tools are getting ever sharper.”

Not content with writing books and giving lectures, Dennett has thrown himself into a number of projects to help him with his research, working with philosophers and scientists alike. One such endeavour was “Cog”, a project undertaken in the 1990s where Dennett and a team of scientists at MIT aimed to create a conscious robot. “That was a wonderful project and started off with amazing ambition and enthusiasm.”

Although Cog the robot didn’t become conscious, Dennett argues that in principle it could have. “One of the interesting things of the Cog project was that it showed – well, it certainly showed me – how easy it is to impress people with the apparent consciousness of a robot.”The team invited someone to shake hands with Cog and she did. And she screamed. “It didn’t feel like shaking hands with a power tool, it felt like shaking hands with a live actor who had a chainmail glove on or something like that...she was shocked at the way Cog’s hand moved and the way his eyes would respond. Very disconcerting.”

Ultimately Cog went to the museum unfinished, but Dennett says that it was a success because it inspired other philosophers and scientists to continue the research. It also raised a lot of questions about what consciousness is, whether it could be replicated and what that would mean. What would happen if a robot became conscious? Dennett’s answer is unequivocal. “If we made a conscious robot we should enter it into the company of persons. We should treat it with consideration and respect.”

Dennett says that work between philosophers and scientists really got going about 25 years ago, when philosophers came out with some bold ideas about how consciousness is in the brain. “It changed the ethos of the sciences. It used to be that you couldn’t write about consciousness until you were on the verge of retirement, a white-haired sage, not a hard-at-work, on-the-rise, lab scientist.” Traditionally the domain of philosophers, all of a sudden a flood of books written by scientists came out on consciousness. “I think they thought – wait a minute, I’ve been thinking about consciousness privately for years, I’m not going to be scooped by a bunch of philosophers. I’ve got to get my theory out there before somebody else thinks of it.” However Dennett thinks that for the most part the books were pretty bad. “It’s churlish to hold their feet to the fire on this issue but I think some of them have privately recognised that philosophers have really changed the game here.”

As for when we are conscious, Dennett says that we have different thresholds depending on what we’re talking about. “The foetus in the womb is sensitive to sound for several months, the mother’s voice is penetrated into the brain of the soon-to-be born, the baby, for a month or two before birth. So when the babies emerge they are already attuned to the mother tongue. Does that require consciousness? Well, yes, of a sort, sure. It certainly requires the capacity to take in auditory stimuli – not just auditory of course – and start shaping the brain.That’s pretty impressive.”

It can take some time for other sorts of consciousness to develop, and even then Dennett says that we are conscious of a lot less than we think we are. “One of the causes of the inflation of our idea of consciousness is that when consciousness of one sort or another lapses, a bell doesn’t ring, a door doesn’t click. Suddenly you’re just no longer there.”

Dennett experienced such a “lapse” in consciousness at a conference he attended recently. He was listening to a talk and his eyelids started to grow heavy. “Every now and then I just realised, wait a minute, wait a minute, time has passed...and what I’ve been doing is sleeping with my eyes half open for a few minutes. You sort of can’t notice when it happens because you can’t see both sides of the boundary. And I think in fact that’s like doing one of those demonstrations that permits you to see that you have a blind spot. We’re completely oblivious to the fact that we have a blind spot in each eye, you have to go to careful lengths to notice your blind spot. But I think we have temporal blind spots all day long.”

Daniel C. Dennett is Professor of Philosophy and Co-Director of the Center for Cognitive Studies at Tufts University. His first book, Content and Consciousness, appeared in 1969.