The below text is from a speech given by Hawking at TED in 2008. He expects that humans will be able to repair and alter themselves, which will create new political issues. That just happens to be the topic of a book I am working on at the moment, so nice to see Hawking bringing it up. Thanks to my fellow H+ board member James Hughes for posting this on the WTA mailing list.
Link to TED talk and transcript.
Life in the Universe by Prof. Stephen Hawking
…I am sure that during the next century, people will discover how to
modify both intelligence, and instincts like aggression.
Laws will be passed, against genetic engineering with humans. But some
people won’t be able to resist the temptation, to improve human
characteristics, such as size of memory, resistance to disease, and
length of life. Once such super humans appear, there are going to be
major political problems, with the unimproved humans, who won’t be able
to compete. Presumably, they will die out, or become unimportant.
Instead, there will be a race of self-designing beings, who are
improving themselves at an ever-increasing rate.
If this race manages to redesign itself, to reduce or eliminate the risk
of self-destruction, it will probably spread out, and colonise other
planets and stars. However, long distance space travel, will be
difficult for chemically based life forms, like DNA. The natural
lifetime for such beings is short, compared to the travel time.
According to the theory of relativity, nothing can travel faster than
light. So the round trip to the nearest star would take at least 8
years, and to the centre of the galaxy, about a hundred thousand years.
In science fiction, they overcome this difficulty, by space warps, or
travel through extra dimensions. But I don’t think these will ever be
possible, no matter how intelligent life becomes. In the theory of
relativity, if one can travel faster than light, one can also travel
back in time. This would lead to problems with people going back, and
changing the past. One would also expect to have seen large numbers of
tourists from the future, curious to look at our quaint, old-fashioned
ways.
It might be possible to use genetic engineering, to make DNA based life
survive indefinitely, or at least for a hundred thousand years. But an
easier way, which is almost within our capabilities already, would be to
send machines. These could be designed to last long enough for
interstellar travel. When they arrived at a new star, they could land on
a suitable planet, and mine material to produce more machines, which
could be sent on to yet more stars. These machines would be a new form
of life, based on mechanical and electronic components, rather than
macromolecules. They could eventually replace DNA based life, just as
DNA may have replaced an earlier form of life.
This mechanical life could also be self-designing. Thus it seems that
the external transmission period of evolution, will have been just a
very short interlude, between the Darwinian phase, and a biological, or
mechanical, self design phase. This is shown on this next diagram, which
is not to scale, because there’s no way one can show a period of ten
thousand years, on the same scale as billions of years. How long the
self-design phase will last is open to question. It may be unstable, and
life may destroy itself, or get into a dead end. If it does not, it
should be able to survive the death of the Sun, in about 5 billion
years, by moving to planets around other stars. Most stars will have
burnt out in another 15 billion years or so, and the universe will be
approaching a state of complete disorder, according to the Second Law of
Thermodynamics. But Freeman Dyson has shown that, despite this, life
could adapt to the ever-decreasing supply of ordered energy, and
therefore could, in principle, continue forever….