Let change happen

From Chrissy Philp

You report that bird species are hopping on and off the critically endangered species list due to changes in habitat ( 16 May, p 6 ).

Does that make change good or bad? I thought that environmental change kick-starts evolution, so it must be good, right? Yet environmentalists behave as if the opposite were true: every time a change occurs that pushes a species nearer to extinction there is an outcry. It appears that past change was good – it created a world of wonders, including us – but that present change is definitely bad.

Can we have it both ways? Can we have a nice safe world where everything is preserved exactly

as it is now, and have evolution too? Are we, perhaps, endangering future evolution with our self-critical and yet self-righteous conservationist ideology?Bath, UK

What is a theory?

From Peter Household

Evolution is not a theory but an established law, according to a quote in your Viewfinder section ( 2 May, p 23 ). Scientists’ use of the term “theory”, it is suggested, inadvertently helps creationists’ argue their case.

Before we can even consider the merits of this line of reasoning, we need agreed definitions of “fact”, “law”, “theory”, “hypothesis” and “conjecture”. Is there a mechanism for achieving such agreement? Should there even be one? And should the everyday usage of the word “theory” influence the debate?

It is entirely possible that any agreed definitions would rule out use of the term “string theory”, and this might, as Lawrence Krauss has argued ( 3 December 2005, p 23 ), prevent further use of the phrase giving comfort to creationists.

Agreement on terms is only the start. In a lecture celebrating New Scientist’s 50th anniversary in 2006, E. O. Wilson suggested that the time has come to regard natural selection as one of the fundamental laws of biology. His implication was that the proposal is controversial. Let the controversy rage and let it one day be resolved – but not just for the sake of expediency in the battle with creationism.

Science is not a church, and has no bishops. We must take the rough of that with the smooth. Mitchelstown, Cork, Ireland

Despite themselves

From Clive Singleton

The potential benefits of spite reported by John Whitfield would not have surprised an Athenian citizen from the 5th century BC ( 16 May, p 42 ).

In 458 BC, the playwright Aeschylus produced his Oresteia trilogy, in the final part of which the avenging Furies are confronted by the goddess Athena. She persuades them to withhold their wrath from Athens in return for an honoured position in the city.

The Furies were considered to be ancient spirits of vengeance who ensured that punishment was meted out to those who broke the natural laws of society. In the play the metaphor is clear: primitive tribal fury is calmed and harnessed to the law to become an engine of justice. The benefit to the city is stated repeatedly and explicitly – hope and kindness can now flourish because cheats and criminals know what is likely to happen to them.

The name Eumenides, with which the Athenians invoked the Furies, means “well disposed” or “kindly ones”. The Athenians clearly had an instinctive understanding of the potential for good contained in public anger, a lesson that certain

British politicians appear to be relearning the hard way.Nailsworth, Gloucestershire, UK

Detect a monopole

From Malcolm Shute

The magnetic monopole virtual particles that you report ( 9 May, p 28 ) are, of course, no more the real thing than holes in a semiconductor crystal are positrons. Admittedly, in the absence of the real thing, the virtual particle can give some idea of a monopole’s behaviour, but no more than this.

If real monopole particles were common in our part of the universe they would be easy to detect with an ordinary electromagnet and some metering in the coil leads. The stronger the electromagnet, the bigger would be its catchment area; and the longer the time it was energised, the more monopoles it would collect.

At the end of the collecting period, we would reverse the polarity of the electromagnet and monitor the meters as the two clouds of monopoles, one from each pole of the magnet, are suddenly repelled, fly the length of the magnet and come to an abrupt halt at the other end.La Tour d’Aigues, Vaucluse, France

Unsatisfying answer

From Tim Wilkinson

The idea of a multiverse is gaining respectability ( 2 May, p 35 ), but while it explains why physical constants have their observed values, it still provides us with no means to predict them from first principles. Since we can imagine other universes, each with completely different physics, the difficult questions have merely been put off to the “next level”.

It is very appealing to conceive of a multiverse where every logically possible universe exists. But I wonder whether postulating

Enigma Number 1549

24 | NewScientist | 13 June 2009

OPINION LETTERS

WIN £15 will be awarded to the sender of the first correct

answer opened on Wednesday 15 July. The Editor’s decision is final.

Please send entries to Enigma 1549, New Scientist, Lacon House,

84 Theobald’s Road, London WC1X 8NS, or to enigma@newscientist.com

(please include your postal address).

Answer to 1543 Pentagony: The perimeter of the pentagon is 99 cm

The winner James Diamond of London, UK

RICHARD ENGLAND

I have written down three different five-digit perfect squares, which

between them use four different digits. Each of the four digits is used

a different number of times, and the four numbers of times are the same

as the four different digits of the perfect squares; I’m not saying whether

any of the digits is used its own number of times.

What are my three perfect squares?

Same four digits