Will we colonise the universe? Are aliens out there? Can computers outsmart us? In a unique interview, Professor Stephen Hawking, who has spent a lifetime applying his formidable intellect to the big questions, gives NIGEL FARNDALE his predictions for the human raceWill we colonise the universe? Are aliens out there? Can computers outsmart us? In a unique interview, Professor Stephen Hawking, who has spent a lifetime applying his formidable intellect to the big questions, gives NIGEL FARNDALE his predictions for the human race
Possibly the greatest, certainly the most famous scientific thinker since Einstein is sitting in his motorised wheelchair grinning at me. ``Look behind the door,'' Professor Stephen Hawking says in his computer-generated, Dalek-like voice. I look. There's a framed black-and-white photograph hanging there, which shows him in the foreground and Marilyn Monroe leaning against a Cadillac in the background. I smile. The superimposition is funny and subtle. Perhaps the professor has just had it done and wants to show everyone. But I suspect he doesn't want to get drawn into a long conversation about it; it's just his way of saying hello and breaking the ice.
All Hawking's conversations are long, even his short ones. He raises his eyebrows for ``yes'', winks his left eye for ``no'', but for the most part communicates via a voice synthesiser at the rate of 15 to 20 words a minute. He suffers from motor neurone disease, a rare condition which degenerates the central nervous system and leads to a wasting of the muscles. It does not affect the brain or the senses. Hawking was first diagnosed with it when he was 21, at which age he was told he had a life expectancy of two to three years. He is now 57.
He has cheated death, but his body is paralysed - apart from a little movement in his twisted fingers. He doesn't type with these so much as apply pressure to two pads, one in each hand, in order to select letters, words and phrases from an index on his computer monitor. He scrolls up and down the screen constantly, at great speed. But, inevitably, the writing process is agonisingly slow. Only when he has constructed the whole sentence or paragraph on screen does he activate his robotic voice to speak it. As a definition of Hell, it would be hard to improve upon the perversity of this predicament: a man with a freakishly quick, brilliant and creative mind condemned forever to articulate his thoughts at the speed of an imbecile.
We've no time for small talk then. I have come here - to Cambridge University's Department of Applied Mathematics and Theoretical Physics, where Hawking holds the professorial chair once held by Isaac Newton - on the turn of the Millennium to ask him what he thinks the future has in store for the human race.
If the world's population continues to grow at its present rate - doubling every 40 years - there isn't going to be enough room for us all on Earth by the year 2600. So will we, I ask, be able to spread out to other planets? His hands go into action. The only sounds in the room are the clicking of the pressure pads and the whirring of the computer. The electronic voice delivers the answer five minutes later. ``We shall probably manage a manned or, should I say, personned, flight to Mars in the next century,'' Hawking says. ``But Earth is by far the most favoured planet in the solar system. Mars is small, cold and without much atmosphere, and the other planets are quite unsuitable for human beings. We either have to learn to live in space stations or travel to the next star. We won't do that in the next century.''
I ask Hawking how fast we will be able to travel on our journey to the next star. Pause. Answer: ``I'm afraid that however clever we may become we will never be able to travel faster than light. If we could travel faster than light we could go back in time. We have not seen any tourists from the future. That means that travel to other stars is going to be a slow and tedious business, using rockets rather than warp drives. A 100,000-year round trip to the centre of the galaxy. In that time the human race will have changed beyond all recognition, if it hasn't wiped itself out.''
Even though there is ice on the ground outside and a bitingly cold wind blowing in over the Fens, Hawking has his window open; his assistant, Chris, has explained to me that this is because the professor thinks better when he's cold. I try to stop my teeth from chattering as I ask whether we humans will keep on changing, or will we eventually reach an ultimate level of development and knowledge? Click click click. ``In the next 100 years, or even in the next 20, we may discover a complete theory of the basic laws of the universe (the so-called Theory of Everything in which quantum theory is unified with Einstein's theory of general relativity), but there will be no limit to the complexity of the biological or electronic systems we can build under these laws.''
I'm just about to ask a supplementary question when the hands start up again. A few minutes pass before Hawking adds: ``By far the most complex systems we have are our own bodies. There haven't been any significant changes in human DNA in the past 10,000 years. But soon we will be able to increase the complexity of our internal record, our DNA, without having to wait for the slow process of biological evolution. It is likely that we will be able to redesign it completely in the next 1,000 years - by increasing our brain size, for example. Of course, many will say genetic engineering on humans will be banned but I rather doubt that they will be able to prevent it. Genetic engineering on plants and animals will be allowed for economic reasons and someone is bound to try it on humans - unless we have a totalitarian world order, someone will improve humans somewhere.''
The professor's predictions - especially his thoughts on improving the human body - seem all the more poignant when you listen to him deliver them in person. Time is even more relative than usual in his company; it actually seems to slow down during those long pauses between my questions and his answers. My interview lasts for four hours, with breaks when a nurse comes in and I'm asked to leave the room. Since the professor had an operation on his oesophagus early last year, the problem he had with food getting into his lungs has been reduced, but he still needs regular suction.
I don't, however, have to leave his room when the nurse comes in to spoon-feed him with an assortment of pills. These are taken with sips of tea which is mostly spilled onto the bib that the nurse ties around his neck. Hawking has thick lips, parchment-smooth skin and a schoolboy fringe, which his nurse parts to one side for him. While all this is going on, the professor patiently continues working the pressure-pads in his hands to compose sentences and paragraphs on his computer screen.
I ask if developing improved humans won't cause great social and political problems with respect to unimproved humans? ``I'm not advocating human genetic engineering,'' Hawking replies metallically. ``I'm just saying it's likely to happen and we should consider how to deal with it. In a way, the human race needs to improve its mental and physical qualities if it is to deal with the increasingly complex world around it and meet new challenges such as space travel.
``We also need to become more complex if biological systems are to keep ahead of electronic ones. At the moment, computers have an advantage of speed but they show no sign of intelligence. This is not surprising as our present computers are less complex than the brain of an earthworm, a species not known for its intellectual powers. But computers' speed and complexity double every 18 months, and this will probably continue until computers have a similar complexity to the human brain.''
But will computers ever show true intelligence, whatever that might be? ``It seems to me that if very complicated chemical molecules can operate in humans to make them intelligent, then equally complicated electronic circuits can also make computers act in an intelligent way. And if they are intelligent, they can presumably design computers that have even greater intelligence and complexity.''
When engaged in conversation with Stephen Hawking none of the usual laws of social interaction apply. After the first few minutes of being with him, however, the long pauses no longer seem awkward. Apart from his big, disarming smile and his expressive eyes - ``twinkling'' seems the most apt, if hackneyed, description of them - there is no body language to help interpret his words.
But the monotone voice does give his utterances an amused, deadpan quality (the voice goes up and down in tone quite musically, but the emphasis it gives to certain words is not necessarily a reflection of their importance in the sentence). Thus, when asked if this increase in biological and electronic complexity will go on for ever, or whether there will be a natural limit, his eyes twinkle, his hands do their frenetic work, and 10 minutes later the voice delivers what sounds like a dry comeback.
``On the biological side, the limit of human intelligence up to now has been set by the size of the human brain that will pass through the birth canal,'' Hawking says. ``Having watched my three children being born, I know how difficult it is to get the head out. But in the next 100 years I expect we will learn how to grow babies outside the human body so this limitation will be removed. But ultimately, increases in the size of the human brain through genetic engineering will come up against the problem that the chemical messages responsible for our mental activity are relatively slow-moving - so further increases in the complexity of the brain will be at the expense of speed. We can be quick-witted or very intelligent, but not both.''
The professor goes on to explain that electronic circuits have the same complexity-versus-speed problem as the human brain and that the speed of light is already a practical limitation on the speed of computers. ``One can improve the position by making the circuits smaller,'' he adds. ``But ultimately there will be a limit set by the atomic nature of matter.
``Another way in which electronic circuits can increase their complexity while maintaining speed is to copy the human brain. This does not have a single CPU [the central processing unit of a computer] that processes each command in sequence, rather, it has millions of processors working together at the same time. Such massive parallel processes will be the future for electronic intelligence as well.''
It's time to ask the big one: will we make contact with aliens in the next millennium? Hawking smiles. His fingers click the pressure-pads. The answer comes seven minutes later. ``The human race has been in its present form for only the past two million years out of the 15 billion or so since the Big Bang. So even if life developed in other stellar systems, the chances of catching it at a recognisably human stage are very small.
``Any alien life we encounter will be much more primitive or much more advanced than us. And if it's more advanced, why hasn't it spread through the galaxy and visited Earth? It could be that there is an advanced race out there which is aware of our existence but is leaving us to stew in our own primitive juices. However, I doubt they would be so considerate to a lower life form. There is a sick joke that the reason we have not been contacted by extra-terrestrials is that when a civilisation reaches our stage of development it becomes unstable and destroys itself. But I'm an optimist. I think we have a good chance of avoiding nuclear war and Armageddon.''
Stephen Hawking has 10 nurses who each do three 10-hour shifts a week. He rises at 7.45am, has physiotherapy, arrives for work at his department at about 11.30am, goes home - five minutes away in the grounds of an all-female college - at about 7pm and is bathed and put to bed by midnight. A nurse turns him over during the night. According to one of the nurses I met, he is a pussycat to work for, always puts people at their ease, rarely complains and hates to be pitied or patronised. One of his friends, the physicist David Schramm, says that he is also an incorrigible flirt: a party animal who likes to dance in his wheelchair. His daughter Lucy says he has an amazing capacity to push those around him to the very edge of physical and mental collapse, while smiling cheekily to himself.
Hawking is well known for his sense of humour - he likes joking about the American accent his voice synthesiser has given him and about his appearances as himself in his two favourite American (``which isn't saying much'') programmes, Star Trek and The Simpsons. His intolerance towards fools is also well documented. There are stories of how he runs over the feet of people who annoy him - and he once went to full throttle and rammed a car that was blocking his ramp. When asked if it is true that he uses his wheelchair as a weapon he will reply: ``That's a malicious rumour. I'll run over anyone who repeats it.''
The intermittent nature of our conversation gives me a good chance to study his room. There is a karaoke machine on the floor and a Marilyn Monroe calendar by the door. There's a Homer Simpson clock on the wall and, next to a row of Russian dolls on a shelf, a Homer Simpson card that says: ``Every time I learn something new it pushes some old stuff out of my brain.'' There is a sticker on the door saying: ``Quiet Please The Boss is Asleep'' - it's all junior common room humour, c. 1973; the professor frozen in time.
Also on the shelves there are photographs of Hawking's children and grandchild. He has said that the thing he regretted most about being paralysed was not being able to play with his children when they were young. His daughter tells a rather touching story of how, as a treat at meal-times, he used to make her laugh by wiggling his ears.
There are also scores of books on the shelves with titles such as The Left Hand of Creation, Quantum Gravity, Black Holes in Two Dimensions and Particle Cosmology. But I can't see a copy of the phenomenally successful A Brief History of Time, which Hawking wrote in 1988. In it he attempted to explain to a general readership his theory of how the universe began. And even though few people have been able to get beyond the first dozen or so pages, it was translated into 65 languages and became one of the biggest selling non-fiction books of all time.
It must have made him very rich indeed. Certainly it has made him famous enough to command fees of about £50,000 for a single public lecture in America and the Far East, and £100,000 for appearing in television advertisements for Specsavers. In all, his commercial endeavours are thought to be worth more than £1 million a year.
We normally associate being rich and successful with living a life of luxury - but what, I ask him, does wealth and success mean to him? ``I may be successful in my work,'' he says through his machine. ``But I'm hardly rich on the scale of people in the City. To lead a reasonably normal life, I need a lot of nursing care - and I won't get that on the NHS. I would be stuck in a home without a computer or much individual attention and I probably wouldn't survive long. So it has been very important to earn enough to pay for my care both now and in the future.''
In 1995 Stephen Hawking married his nurse, Elaine, the former wife of the man who invented his voice synthesiser. It was the same year he divorced Jane, his first wife and the mother of his three children. Stephen had met Jane at a New Year's Eve party in 1962, just as his illness was beginning to take its toll, and he married her three years later. Last year she wrote an autobiography, a damning account of her life with Hawking. In it she alludes rather cruelly to the complicated nature of the couple's sex life; she also describes herself as a ``drudge'' and her husband as ``a masterly puppeteer'' sometimes made despotic by the combination of public adulation and an illness that left him as helpless as an infant.
She received little thanks for devoting her life to caring for him, she wrote, and often came close to suicide. In the early 1990s when it was obvious their marriage had broken down, she had a discreet affair with a Cambridge choir-master who eventually moved into the Hawking household, apparently with Stephen's tacit understanding. But a 24-hour nursing team also moved in and Jane accused them of dressing provocatively and trying to manipulate her husband emotionally.
Although Professor Hawking does not comment on his first marriage, claiming never to have read Jane's book, he does reflect that: ``There are aspects of my celebrity I don't like, but it would be hypocritical to complain. I can generally ignore it by going off to think in 11 dimensions.''
Stephen Hawking was born on January 8, 1942, 300 years to the day after the death of his hero, Galileo. He was brought up in St Albans and was in many ways a normal, clumsy, inky-fingered child - except that he used to make fireworks and cannibalise television and radio sets to build computers, before computers had really been invented. He also had handwriting that was so bad it was unreadable and a stutter that he inherited from his father, a medical researcher described by one family friend as a disconcerting eccentric with below-average charm.
At Oxford, Stephen Hawking never attended lectures, soon realised he was intellectually superior to his tutors and grew bored with life. He took a first in Physics, but only after a viva revealed his genius for problem-solving and his contempt for course work. It has sometimes been suggested that had it not been for his illness Hawking might not have focused his mind and gone on to make the contribution to science that he did. It galvanised him and forced him to solve problems not on a blackboard but geometrically and pictorially in his head - in 11 dimensions.
It is tempting to read much into the paradox of his condition: a pure mind wandering the universe while trapped in a wasted body. Like Milton's blindness or Beethoven's deafness, it seems at once heroic, tragic and romantic. But Hawking dismisses the description. ``I have never felt myself as a perfect soul living in an imperfect body. Although I may take pride in my intelligence, I have to accept that the disability is also part of me.''
Yet if we have souls, his is surely a romantic one. He loves listening to Wagner. And he refers to his longing to discover, through physics and cosmology, the mind of God. His friends say he sometimes feels a crushing sense of loneliness - even though he rarely experiences the luxury of being on his own. I ask him if he has any recurring dreams. ``I think I dream a lot, but normally I don't remember what I dream. One dream I do remember is being in a hot-air balloon. For me the balloon is a symbol of hope. I first had the dream at my lowest point when I caught pneumonia and had to have a tracheotomy operation that removed my power of speech.''
That was in 1985. His condition then was so bad that his first wife was asked to give her permission to switch off his life support machine. She refused. Presumably Hawking didn't expect that he would still be around to see in the new millennium? ``No,'' he says. ``But now I would be disappointed if I didn't live long enough to be sure that there was indeed a picture into which everything fitted.''
I've heard Professor Hawking described as many things: a bloody-minded genius, a witty manipulator, a prima donna. But what three words would he use to describe himself? There is a long pause before that unemotional computerised voice penetrates the icy Cambridge air: ``Determined, optimistic and . . . I can't think of a third. My wife would say stubborn, out of touch with reality.''
I leave as I came in four hours earlier, with a smile on my face.