Letters : . . .
by e-mail
You are at it again. Last month you talked of the “illusion of moral judgment
and free will” (Editorial, 22 March, p 3). Now you say that “our brains keep the
illusion of conscious control alive only by constantly `backdating’ the chain of
events so that they make sense”, and that “a tennis player . . . experiences
hitting a ball long after the ball has flown back over the net”.
Of course we do not, cannot and would not want to consciously control every
detail of our actions. So, in this narrow sense, your conjecture is right. But
one consciously chooses to play tennis, decides on strategy, changes tactics and
so on during the match.
Where is the evidence for the speculation that free will or control is an
illusion?
Letters : . . .
Peterborough Northamptonshire
Your editorial about belief in the soul raises an interesting
question about the nature of irrational belief.
Richard Dawkins described religion as a “mind virus”, a meme with
powers of replication. However, has anybody considered whether the “religious
need” actually has a physical basis in the brain?
If atheists (or believers) are born rather than made, like left- or
right-handers, it would at least explain the odd consistency in the US survey of
religious scientists. If the predominance of “rationalism” or “mysticism” in a
population were genetically determined, it would also explain why such beliefs
appear to be independent of evidence, intelligence and levels of education.
The possibility that there might be genes for addictive personalities,
criminality or sexual orientation seems insignificant alongside the possibility
of a gene for religious belief. Of course, even if it were shown to exist, 40
per cent of US scientists would feel bound to deny the evidence.
Letters : Irrelevant spectre
Derby
Carlo Bassani cites the spectre of Bhopal to gain support for retaining the
Facility for Investigating Runaway Events Safely (FIRES) through public funds
(This Week, 29 March, p 12).
However, greater understanding of the chemistry of methyl isocyanate was
irrelevant to the disaster at Bhopal. It was well understood that the substance
was extremely dangerous鈥攖his is clear because many safety features were
built into the plant. What matters is why these safety systems failed.
In any case, the process design was flawed, in that there was no need for
bulk storage of methyl isocyanate, which could have been manufactured as it was
needed.
Public support is perhaps needed for research into why the wealthy chemical
industry believes it needs public subsidy to push chemical technology to even
more deadly and marginal extremes.
Letters : Insult to insects
New Mills, Derbyshire
I refer to the vertebratist chauvinism that failed to acknowledge in these
columns that flight was invented by insects, quite properly corrected by Mark
Harvey (Letters, 29 March, p 53).
I’ve nothing personal against fish, amphibians or even birds, you understand,
but it’s already hard enough to get popular science communicators to accept that
insects and other arthropods were the first animals to emerge from the famous
primeval ooze onto dry land.
In fact, of course, they were the long-established food supply that tempted
our slimy but noble ancestors out of the water in the first place.
Notice my careful political correctness. I said the “first animals” on land,
not the often-heard “first life” on land that annoys botanists.
So-called spineless creatures everywhere, stand up for your rights! On any
number of legs to suit your personal preference, of course.
Letters : . . .
London
According to Michael Crawford and David Marsh in their book Nutrition and
Evolution (published in Britain as The Driving Force) eating
insects (providing chitin rather than heavier calcium) would eventually mean
lighter bones. I wondered if this would be worth adding to the considerations
about the origin of flight (“Birds do it . . . did dinosaurs?”, 1 February, p
26)?
And what about the article that suggested early chimpanzees went up into the
trees, rather than man coming down (New 杏吧原创, Science, 29 March, p
18)? Crawford and Marsh suggest the same thing, giving as their theory that
Homo sapiens evolved in a nutritionally very rich land-sea interface (they
suggest the term Homo aquaticus). This meant that they were able to
keep the same relative brain size from their earliest beginnings, while any
species that headed further in land (such as our relatives that headed
treewards) suffered brain shrinkage relative to size.
Letters : . . .
Sussex
Simon Easteal and his student Genevieve Herbert may have come up with the
idea that an ancestor of the chimpanzee walked upright, but they are not the
first to do so. This proposal was first put forward by myself and Jeremy
Cherfas, then of the University of Oxford, in the early 1980s. We then
elaborated on the idea in our book The Monkey Puzzle (Bodley Head,
1982), where we went further than the suggestions covered in your report by
suggesting that, in everyday language, instead of mankind being descended from
apes, apes are descended from mankind.
Letters : Electrons for grabs
Cardiff
If particle physicists are set to reject the electron on its 100th birthday
(“Time to die . . .”, 5 April, p 32), may physicists who believe that fields are
fundamental restate our claim to it?
Interaction at a distance of compact particles, via the exchange of other,
highly transitory particles, has long appeared esoteric to followers of
Maxwell’s classical theory. So the upsetting results from the Hamburg
accelerator experiments give us good reason for returning to Hendrick Casimir’s
model of the electron.
Casimir predicted attractive forces between parallel conducting plates
through waves of the “vacuum” field being lower in the gap (New
杏吧原创, Science, 25 January, p 16). In 1948, he analysed the effect in
terms of quantum vacuum fluctuations filling space, but the same formula was
obtained in the 1960s on Max Planck’s model of zero-point fields, as
hypothesised in 1916 by Walther Hermann Nernst.
After his study of parallel plates, Casimir tried to model the electron as a
conducting shell of charge having repulsive Coulomb forces balanced by the
Nernst-Casimir force. Though Casimir failed, modern developments of the
zero-point field approach have resurrected his model (The Quantum Dice
by Luis de la Pe帽a and Ana Maria Cetto). The dimension of the electron
field-bundle is of the order of the Compton wavelength or even as big as an
atom.
Particle physicists are concerned with much smaller objects, so let them now
drop their claim to the electron.
Letters : Signalling green
Denbighshire
Philip Ball, in his article on blue LEDs (“Into the blue”, 29 March, p 28)
reports the unveiling of a set of traffic lights using green LEDs in Japan in
December 1995, but readers may be interested to know that the late John d’E.
Stowell and I built a set of railway signals using gallium nitride green LEDs
during the summer of 1995.
These were brought into use at the Deeside signal box on the Llangollen
railway (a heritage steam railway in North Wales) in October 1995 and have
operated without failure ever since. Despite the fact that the green diodes were
only one tenth of the power of the yellow and red diodes, they are clearly
visible for 100 yards in sunlight, yet consume less than 1 watt.
To the best of my knowledge the signals at Deeside are the first practical
application of LEDs in railway signals, but their development was prompted
merely by necessity: we could not afford the 拢2000 needed to bring mains
power to the Deeside signal box, which consequently had to be powered by
batteries.
Letters : Fax me another
Brussels
You find it amusing that a Dell customer who couldn’t get his computer to fax
anything was trying to fax a piece of paper by holding in front of the screen
(Feedback, 5 April)
But of course he was right. It was the computer that was moronic, not the
person. That is exactly how we should be sending documents or pictures.
Letters : Anyone for free will?
Cambridge
You argue that Descartes’s notion of the mind as an entity distinct from the
body “no longer seems to fit the facts” (Editorial, 5 April, p 3). Actually,
there is no difficulty in reconciling work on the timing of neural events in the
brain with the sense you describe that “our conscious self sits inside us,
looking out on the world”: the difficulty only arises if we also suppose that
this conscious self is capable of initiating actions.
A very good case can be made for “one-way Cartesianism” in which the real
“we” observes the world, but cannot act on it, being carried round in our head
like a tourist in a rickshaw. The reason for our illusion that we can will
things to happen is that we see our own actions being planned before they
happen, but not other people’s.
The idea is expounded further at
http://www.cai.cam.ac.uk/subj/medicine/roger.html.
Letters : Charity balls
Leeds
It is suggested that “opting out” schemes may be introduced for the use of
human organs after death (This Week, 5 April, p 5). While I’m sure that many
people would be happy to know that the organs they donate will be used for
research or teaching in reputable academic institutions, fewer would wish their
remains to be fought over by the vultures and jackals of the pharmaceuticals
industry.
This prospect might be sweetened if the donor were able to nominate a charity
to receive fixed donations for any body parts utilised, with the administration
of the scheme jointly funded by the organisations involved. While commercial
outfits would make the payments, these would be waived for academia.
I for one would be content to lie partially in my grave with the certitude
that the British Heart Foundation had received 拢50 for my absent heart, or
Amnesty had made a couple of quid from my testes.
Letters : Case against cadmium
London
Andy Coghlan is right to raise potential problems associated with the grazing
of animals on land contaminated with cadmium, and the possibility that offal
from them might contain high levels of the metal (This Week, 22 March, p 4).
However, the article does not mention that cadmium is a cumulative poison, is
strongly suspected to be a human carcinogen, and most importantly, is able to
pass through the skin into the circulation from soil or water.
While we can choose what we eat and avoid vegetables and meat originating
from contaminated areas, control of substances passing through the skin is much
more difficult. How much cadmium remains in the soil or seawater following
discharge of 3 million tonnes of toxic waste each year from Britain alone?
Uptake of cadmium through the skin poses many problems. Though there is no
evidence that it promotes skin cancer, progressive uptake of the metal may pose
carcinogenic risks to the prostate or kidney. A major effect of cadmium in the
body is its ability to reduce the bio-availability of essential trace metals,
notably zinc. Zinc is an essential constituent of all living cells, albeit at
minute concentrations.
Our experimental studies have demonstrated that cadmium absorbed into the
skin severely inhibits zinc metabolism. A massive reservoir of unusable zinc
accumulates in the tissue. Over a prolonged period, this diversion of zinc can
be expected to lead to hair loss, thinning of the skin and delays in wound
healing. However, the extent to which these problems actually occur in people
living or working in areas heavily contaminated with cadmium is unknown at
present.
Perhaps it is time for new studies, noting health trends in fishermen
employed in contaminated estuaries or contractors working in landfill sites?