Turing was there
I enjoyed your interview with Stephen Grand, creator of norns鈥攕ome of
the most sophisticated artificial life around
(1 April, p 42). However, I found
his bald statement that artificial intelligence has failed because Alan Turing’s
predictions about it have not come to pass a little glib.
Grand proposes the use of genetic algorithms and a biological approach to
solving the AI problem鈥攖he very same things which Turing himself proposed
way back in the 1940s. Turing discussed “genetical” searches and unusual neural
network architectures, and carried out some of the first work in a field which
has since become known as morphogenesis.
For a small example of functional Turing nets (to our knowledge the world’s
first) see http://home.clear.net.nz/pages/cw/unorganized.htm.
The development of the programmable digital computer based on Turing’s
designs so eclipsed these ideas that they have been more or less forgotten. If
Turing hadn’t died at the age of 42, or if these ideas had been developed, the
world might have been quite a different place today. We would probably have more
than just Macs and PCs on our desks.
Net nurse
I took exception to the Netropolitan column
(25 March, p 17) which warned of
patients handing “reams of laser-printed Web pages” to their GPs and declared:
“It can only get worse.” As far as I am concerned, it can only get better.
Without the Net, I would not have had access to the full symptoms of coeliac
disease, which aided in my diagnosis in 1997. The medical dictionaries were
rather vague.
I succeeded with self-diagnosis in the face of my GP’s insistence that I was
either too young for the condition, or suffering from “tension”. I look forward
to the day when filling in a computerised multiple-choice paper is the first
stage in a doctor’s diagnosis. We might then avoid the “intuitive” assumption
that persistent patients are hypochondriacs, and the supposedly scientific
diagnosis of catch-all “syndromes”.
Fat facts
In the article “Cut the carbs”
(18 March, p 26) Katherine Milton seems to
have misunderstood our research, suggesting that we support eating fatty
domestic meats. Nowhere in our original manuscript do we make this
contention.
Our take-home message was that hunter-gatherer diets are higher in protein
and lower in carbohydrate than current Western diets鈥攐r dietary
guidelines鈥攁nd that this macronutrient balance may provide insight into
potentially therapeutic diets. If there were any inference, it would be that
dietary fat should emulate fat sources found in game meat and organs (high in
omega-3, low in omega-6 and high in monounsaturates).
Raising consumption of low-fat dietary protein at the expense of
carbohydrates has been shown to improve blood cholesterol, triglycerides and
homocysteine levels and thereby reduce the risk of coronary heart disease.
Further, increased dietary protein has been shown to improve insulin metabolism,
promote weight loss and have beneficial effects for breast cancer patients.
Consumption of low-fat dietary protein at the expense of carbohydrate is the
nutritional pattern consistent with our evolutionary history and represents a
viable option for improving health and well-being in modern people. We do not
advocate diets containing large amounts of saturated fat such as the Atkins
Diet.
Finally, I was misquoted as saying that humans lack the enzyme to synthesise
taurine from precursor amino acids. My point was that humans have a reduced
ability to synthesise taurine from cysteine, an adaptation similar to that found
in obligate carnivores.
Letter
Evolutionary theory seems to have been misused again, this time to predict
the ideal human diet. Even if the diet of early humans has been accurately
reconstructed, it does not mean that it is the best one for today’s humans.
Selection against death by heart disease, type II diabetes, and other diseases
of middle age and old age would not have happened: early humans did not live
long enough.
Anyway, few animals (or plants) are perfectly adapted to their ecological
niche. An example of the mismatch between the best diet and the environmental
diet, well known to biologists, is the fruit fly Drosophila
melanogaster. In the wild they apparently live on yeast, some bacteria, and
fermented vegetable or fruit juices containing some alcohol and usually very
little sugar. This high-fat, high-protein, low-carbohydrate diet is analogous to
the diet proposed in the pro-meat article.
Up to 95 per cent of the energy from standard diets in the lab is in the form
of carbohydrate, as maize meal and purified sucrose or glucose. On this diet the
flies’ fecundity and longevity exceed those on a more natural diet by 100 per
cent or more.
The work of Kerin O’Dea on Australian aboriginals does not show that the bush
diet was good, merely that the bush diet was better than their urban diet, which
was dominated by Coca-Cola and fried potato chips. The Australian aboriginal has
a very poor life in Australia, with a life expectancy typical of Third World
countries. Those who live in Western conditions on a Western diet live a lot
longer.
Super sunscreen
Is this a totally daft idea? Presumably global warming could be reduced if
some Earth-bound solar radiation were dispersed. Equip a spacecraft with the
means to blow bubbles from a suitable material. Place it in a yearly synchronous
orbit around the Earth (about 2 million kilometres radius) and locate it between
the Sun and Earth. I have no knowledge about blowing bubbles in space but
speculate that in a vacuum and under zero gravity conditions one could create
some whoppers, which one would need to do to create a dispersal area of a
reasonable fraction of the projected area of our planet.
Deaf dialogue?
Rob Edwards’s healthy scepticism about “stakeholder” dialogue is welcome
(1 April, p 45), though only relevant to certain cynical “greenwash” exercises. But
I would like to correct some possible misconceptions about the “secret” talks
between British Nuclear Fuels (BNFL) and green campaigners that Edwards brands
as an excuse to exhaust and divide the opposition.
First, the BNFL “national dialogue” is not secret. The first stakeholder
meeting was reported in The Guardian the very next day.
Secondly, the dialogues we run are about finding sensible and sustainable
ways forward that people can then implement, rather than producing reports or
articles for the file.
Thirdly, the dialogue is under the control of the participants, not any one
party. It is up to the participants or stakeholders collectively to decide the
issues they wish to address, the information they need, who else to invite and
their work programme.
Fourthly, there are more than just environmental stakeholders in the BNFL
dialogue. It includes, among others, representatives from trades unions,
communities, local authorities, government departments, customers and
regulators.
Finally, Edwards contends that such a dialogue is not about changing the
world but keeping it the same. Is this really the case? How does he propose
change should happen? How should large organisations facing complex and
difficult environmental issues best engage with civil society? Through an
omniscient nuclear Tsar (I’m sure Rob would agree with his or her every
decision)? Telepathy? Traditional write-me-a-clever-paper-and-I’ll-ignore-it
consultation? Surgical brain implants?
Not only do we have to talk about the sorts of issues raised by companies
such as BNFL, but we have to talk effectively. That’s what a genuine stakeholder
dialogue aims to do. If the stakeholders think the dialogue is going off track
or isn’t delivering, then it is up to them to change it.
Letter
I am so grateful to Edwards for pointing out that I鈥攁 co-founder of
both Friends of the Earth and Greenpeace鈥攈ave been engaged in a
“meaningless charade” for the past 18 months. Silly me. Thanks, Rob. I’ll resign
immediately and go back to lobbing bricks.
Green organisations have never been a united “movement”. If divisions have
been exposed during the process, then perhaps it will serve to show that a
healthy diversity of opinion exists within the green ranks. This is about the
route to take in achieving a common goal, rather than in the definition of the
goal itself.
Breathtaking
Reading of the discovery that frequent use of paracetamol can aggravate
asthma
(25 March, p 5), I wondered whether anybody is looking for a correlation
between increasing sales of paracetamol linctus for children and the perplexing
rise in the incidence of asthma in recent years?
Phone plea
Iridium may have failed because it was too expensive
(25 March, p 3, and
8 April, p 65), but the technology and the solution鈥攁nd similar
systems鈥攁re the best that those of us who live and work in large areas of
Australia, Africa, South America and enormous parts of Asia can get.
Cellphones have definitely not “expanded to cover the majority of locations
people want to phone from”. They have merely expanded to cover those small areas
where there is sufficient population density and affluence for cellphone
companies to make big profits.
Cellphones will never provide any decent coverage in the remoter parts of the
world. Boasts about covering large percentages of population are meaningless if
you are an exploration geologist in central Australia, a villager in central
Africa or a scientist in Antarctica.
Iridium was not a white elephant. It was just too expensive for its most
needful customers to use. Rather than let this very workable system crash and
burn, organisations such as the UN should be taking it on and providing phones
to those areas where the market economy never will.
Sea food
Nitrogen is essential in the growth of phytoplankton and the maintenance of
the health of the ocean. Your editorial of
8 April (p 3) oversimplifies the
issue of managing climate change discussed in the article by Fred Pearce
(p 18).
It refers to nitrogen as an ocean pollutant and like many substances, when
present in excess this is true. The editorial cites cases where too much
nitrogen has been unintentionally poured into the ocean, with unpleasant
impacts.
Our studies show this will not be the outcome of adding nitrogen to selected
parts of the ocean which are nitrogen deficient. We will need more food for the
increase in the world population that is expected. Careful nourishing of the
ocean is a very attractive way of turning an industrial waste
product鈥攃arbon dioxide鈥攊nto harvestable fish, by adding the
nutrients missing from the base of the food web.
The technology disparaged in the editorial is about providing the nutrient in
the correct place and concentration. It is much too simple to call nitrogen a
pollutant in this case.
Quantum query
We are told that a conscious observer is required to collapse the wave
function in quantum experiments. Could this form the basis of a test to see if
the up-and-coming intelligence of computers is really conscious?
Safety scare
Continuing the discussion on speed
(15 April, p 40), it is well known that
people often drive according to the condition of the car. Fitting automatic
braking systems tends to boost speeds because drivers’ confidence in their
brakes increases more than the actual improvement in braking efficiency. My
solution would be to remove drivers’ safety belts and to place a large spike in
the centre of the steering wheel.
Dome bones
I recently returned from a school visit to London’s Millennium Dome. I was
astonished to notice in the cavern inside the Body Zone housing the much
publicised beating heart, that the overarching ribs emanate from two separate
spines, one on either side of the floor, and that each spine alternates ribs and
vertebrae. Overhead, the ribs do not meet in any kind of sternum. It would be
difficult to devise a more inaccurate travesty of a ribcage.
Correction
In
“Life force” (15 April, p 20), we mistakenly wrote that
mathematician Lov Grover is in the IBM research division. He actually works for
Bell Labs in Murray Hill, New Jersey.