No reflection
It may well be that a sense of self is essential to our intellectual abilities (24 August, p 16). But why should this involve an ability to recognise one’s own image? For all of prehistory and most of history, people only encountered their own image on rare occasions, and in imperfect form. Reflections from water, for example, would tend to be faint and ripply. It is only in the past few hundred years that good-quality mirrors have become widely available.
Frequent impacts
Some astronomers claim that three Tunguska-sized events occurred over land last century (17 August, p 12). Since water covers 70 per cent of the Earth’s surface, it seems likely that there is roughly one such event globally every 10 years or so. Some vessels inexplicably “lost at sea” may have been in the wrong places at the wrong times.
Ancient civilisations had folk memory to explain why they should be fearful of cometary portents. Perhaps we should keep our fingers well crossed.
Jeff Hecht writes: If all three events on land in the last century were Tunguska-sized, it would be reasonable to extrapolate to about one event a decade over the planet as a whole. However, nothing close to that scale has been detected since military satellites began monitoring the whole planet in the mid-1970s. The largest event detected by satellites occurred on 1 February 1994, with an explosion of between 50 and 200 kilotons, far short of the estimated 10 megatons of Tunguska.
Civilian asteroid specialists have doubts about two of the events 鈥� those over Brazil and central Asia 鈥� because of a lack of physical evidence. If the events did happen, they may have involved objects smaller than the Tunguska one but still large enough to produce a blast noticed on the ground. Asteroids come in all sizes, and there’s a big difference between the 50 to 60 metres estimated for the Tunguska object and the 10 to 15 metres estimated for the 1994 object.
Reading dirty plates
We would question claims by Barry Fox that the congestion charging system being installed by Transport for London “could be a lot easier to cheat” (17 August, p 14).
The fact is, lengthy and rigorous tests of the camera system being installed 鈥� which, incidentally, is similar to that now being used successfully in Melbourne, and other places around the world 鈥� have shown accuracy rates of 90 per cent on vehicles passing a camera. If they pass more than one camera, as virtually all of them will, that capture rate rises to 95 per cent or more.
It should also be borne in mind that the cameras are for enforcement purposes only. The cameras are not part of the means of paying the charge
Those who might think they can cheat the system would do well to note that Fox’s claims are based on research that is four years old.
Also, since it is illegal to tamper with a number plate, it is a little mischievous for the British Automobile Association to claim that, “The honest motorist with nice clean plates will be subsidising the people with dirty plates who don’t pay.”
Letter
If traffic cameras fail the eye test, then their life will not be made any easier by the Driver and Vehicle Licensing Agency’s new mandatory font for licence plates. This appears to have been designed 鈥� or rather, thrown together 鈥� by someone with no understanding of the factors that aid legibility and no artistic sensibility, or even sense of style. The curves that help to distinguish one letter from another have been squared up, and closed forms have been used for the digits 6 and 9.
As a result, one blob of mud can convert a 3 into a 9, a 6 or a 9 into an 8, a C into a G or an O into a Q. Two blobs of mud can convert an O into a D (as your picture showed) or an 8 into a B. I can foresee many drivers risking the law and artistically decorating their number plates with strategic mud. Readers can see the new font at . Incidentally, customised plates, for example, those with an italic font, are now illegal.
Heated bees
Anton Stabentheiner has noted an increase in temperature that bees show when they are being subjected to a “smell test” by guard bees (17 August, p 25). However, it seems more likely that the increase in temperature is a consequence of the bee alighting after its flight.
As a bee flies, heat will be dissipated by airflow, but when the bee alights, it seems likely that its temperature will rise, since airflow will be significantly reduced. Has Stabentheiner’s team monitored bees landing on other occasions (both on their own or in the presence of other hive members) after flights of similar length? Do these bees show a similar rise in temperature?
Anton Stabentheiner writes: The heating phases of the bees we examined do not only occur shortly after landing. The delay between landing and the start of the heating phases can be from seconds to several minutes, and the heating phases can also be observed on the combs inside the colony 鈥� guards are active both as “border officials” and “hive police”.
Bees alighting at the hive entrance or on a flower do not usually show an immediate increase of the thorax temperature. Many of them actually decrease the thorax temperature after landing, as was also observed repeatedly in our bees. This is because upon landing, the bees switch from alternating contractions of the flight muscles to simultaneous contractions for the purpose of endothermic body temperature regulation.
Space alert
Your headline states “US military wakes up to asteroid risk” (17 August, p 12).
The US military did not just recently “wake up” to this risk. They’ve been aware for a long time that it helps them make a case for developing space-based weapons, which they are very keen to promote under any pretext they can find.
Still open for business
As president and psychiatrist-in-chief of McLean Hospital, I was surprised to read that McLean had closed (27 July, p 63). Fortunately, we have stuck to our mission and are currently quite healthy, and definitely not closed. Indeed, we are treating more people than ever before, teaching more students than ever before, and doing more research than ever before.
Most importantly, we still treat the whole person, doing so with a full spectrum of psychosocial and biological treatments, whether old standards or recent innovations. Most outcomes, measured by symptoms or satisfaction, are good.
Psychiatry, like any medical approach, can do harm if not practised well. However, it offers great power to help people. That power can and is being used well at many fine institutions, McLean among them.
Radio days
Tim Roberts asks if we are transmitting signals to ETs as part of the SETI@home program (17 August, p 27). Many of my friends on the Ixion email list are running the SETI@home screen saver on their PCs. This has led to discussions of the relative merits of using spare CPU cycles on this project instead of the search for a cure for cancer or any other, more domestic, task.
In the course of the discussions, we decided that there is only a very narrow window of opportunity to spot alien civilisations by their radio emissions.
In our own civilisation, high-power radio broadcasts are slowly being phased out. Fibre optics, cables and beamed signals are less prone to interference, more secure, demand less power and allow greater bandwidth. Less and less of our communication is in a form that will “leak” out of the Solar System. Ham radio might reach another solar system 鈥� a modern mobile-phone signal won’t.
It is not unreasonable to assume that any civilisation significantly more advanced than our own will have perfected its communication systems to the point of zero detectable leakage. So we should concentrate any searches not on alien versions of The Archers but on deliberate signals.
There is an upside: we broadcasted golden oldies like The Goon Show while radio was in its prime. More recently, shows such as Temptation Island, for example, were beamed to a narrow satellite footprint and probably won’t escape the Solar System. So it could be said that those signals broadcast in the short time span between the discovery of radio and the development of non-leaky communications are the best a civilisation has to offer.
Myth of autonomy
There was a revealing slant to the article about how our opinions 鈥� and specifically our voting intentions 鈥� are influenced by our neighbours (24 August, p 42). I was especially struck by the suggestion that free speech needs to be abolished because “it’s undermining democracy”.
I realise this was a joke, but it betrays an important cultural bias in the English-speaking world, namely the myth of the autonomous individual. This ideology is what gave us Margaret Thatcher’s notorious remark that “there is no such thing as society”, and it manifests itself these days in the unilateralism of US foreign policy.
Other cultures do not have the same illusion about the autonomy of individuals. For example, German political commentary, and indeed the German federal constitution, explicitly recognise the process of “opinion formation” or “intention formation” (Meinungsbildung or Willensbildung), and free speech is valued precisely because it makes an essential contribution to that process. It might do the world some good if our views were influenced by the views of our neighbours.
Let's go solar
Before we adopt any new methods for harnessing wasted energy, we should make the most of existing technologies (3 August, p 36).
Almost all the buildings in Greece and Turkey have solar panels on the roof (mainly for heating water, I admit). Yet you won’t see this technology in use anywhere if you go to California.
The British government gives out 拢10,000 grants to homeowners to replace their roofs with solar tiles, but this means you must spend at least another 拢10,000 to meet the full cost of the work involved. If these solar roof tiles are as good as a recent television programme claimed, and you could feed your excess electricity back into the national grid, why don’t the British and US governments insist that all new buildings are fitted with them?
Summit complexities
Your two-page editorial discussing the problems underlying the World Summit clearly states one side of many complex issues (17 August, p 6).
Not everyone in Burundi will agree that refrigerators in their country should never be very large, or indeed, that sustainable development requires that their grandchildren will be the first to have refrigerators of any size.
“We need to incorporate the value of environmental assets into economic theory,” you say. But we do. Economics textbooks discuss the pricing of the by-products of economic activity that are called “externalities”. It’s always possible to arrive at a price for any environmental resource, but politics make it impossible to give or accept payment.
You also say that a power company’s profits do not reflect environmental costs. This is not the case in the US, where power plants must use 鈥� and account for 鈥� expensive pollution-control equipment. Detailed laws and regulations constrain new plant designs with regard to both energy sources and production methods.
Your digression on international trade confuses the need to alleviate poverty with sustainable development. If African farmers make more money, they are quite likely to use whatever their governments don’t take to buy televisions, fridges and other life-enhancing, energy-consuming goods. How many consumers, in any country, let morality determine what they buy?
You call the US “isolationist”. Current US policy 鈥� send the posse anywhere in the world to catch ’em and kill ’em 鈥� may be “imperialist” or “unilateralist” or “interventionist”, but it is surely not “isolationist”.
“Sustainable development is seen by the more enlightened in government as the most significant political, social, environmental and cultural challenge of the moment” is how you begin your peroration.
Perhaps you meant “for the future”. There are many in government, some of them enlightened, who can argue, not unreasonably, that war and peace, terrorism, replacing corrupt politicians or spreading democracy, are the significant issues of the moment.