Domestic threats
Peter Neumann is right to qualify the threat posed by jihadis returning from Syria; their motives are quite distinct from those who attempt terrorist activity within the UK (5 July, p 24).
However, all such jihadis have one very significant impact on return: their credibility among their peers is hugely increased.
The effect of this is twofold. It encourages like-minded persons to pick the same path unless they can be discouraged, as Neumann suggests, but more significantly, it induces stay-at-home militant peers to become more inclined to commit domestic terrorism.
UK government policy, legislation and the populist media’s outrage all make it impossible to have reasoned dialogue with returnees or other militant dissenters.
Sadly, Neumann’s hope that community leaders can rise to the challenge is misplaced. Just as the UK Muslim establishment fails to address the needs of disaffected converts, so it will fail to bring returning jihadis back into the fold.
Instead, exclusiveness in mosque management, intolerance of rival factions, the driving of dissenters underground and fear of open debate all conspire to push would-be jihadis and domestic terrorists out of sight. All four spokes of this circle must be broken before the threat of domestic or returning militants can be countered successfully.
London, UK
Grain of truth
To establish how many people could benefit from a wheat-free diet, and why (12 July, p 28) it seems that much more work needs to be done.
For the time being, science can’t support or refute the proposition that a significant number of people could benefit from such a diet, but as a matter of common sense, it may be unwise to rely too heavily for your nutrition on any one foodstuff.
We can speculate that as knowledge advances, many foods may turn out to have a detrimental side as well as a beneficial one, especially if eaten with extreme frequency, as wheat tends to be in the West.
Cardiff, UK
Going underground
Michael Slezak explores Australia’s ambitions for turning its northern tropical land into a new food bowl (12 July, p 6).
Concerns have rightly been raised about diverting rivers and building dams to irrigate the land, and the environmental impact of these interventions, not to mention the permanent changes this would entail for the indigenous Australians in these territories.
Rather than building dams and reservoirs on the surface, underground systems that capture and store seasonal rainfall should be explored. They might be more costly, but their long-term environmental impact would be less.
Water stored underground would not suffer from evaporation, and there is ample solar energy to power pumping systems. Tokyo’s amazing is a case in point in what can be achieved on a grand scale, but smaller systems serving farming communities offer an alternative to the tried-and-tested methods outlined in your article.
Bray, Wicklow, Ireland
Therapist talking
Richard Layard and David Clark rightly point to the good that has been done in the UK by the Improving Access to Psychological Therapies (IAPT) initiative (12 July, p 24), but this only tells half the story.
Cognitive Behavioural Therapy (CBT) and similar therapies currently available through the National Health Service (NHS) simply aren’t suitable for all psychological problems that patients present. Many of the patients I see have been failed by CBT; to them it can seem as if they are the ones who have failed.
In my opinion, experienced psychotherapists who are able to choose from a wider range of therapies are more likely to help people than are newly trained therapists whose choice is restricted. Experienced practitioners may choose therapies not yet endorsed by the National Institute for Health and Care Excellence, but that lack of endorsement is more a reflection of the very limited number of studies that have been carried out.
A more radical approach would surely involve a better understanding of all therapies, and the ability to optimise treatment for each individual patient. Those with psychological issues who are dependent on the NHS, especially those who cannot work, are effectively being deprived of the full spectrum of treatment options that could be made available to help them.
Layard suggested that mental illness costs UK society nearly 拢130 billion per annum. This is more than the entire budget of the NHS, so shouldn’t mental illness be taken more seriously?
Stansted Mountfitchet, Essex, UK
No small business
You reported the US Supreme Court’s decision that some companies can refuse to provide employees with healthcare plans that offer free birth control. It’s important to note that “closely held corporations” are not restricted to just small or family-owned businesses (5 July, p 6).
According to the Internal Revenue Service, a closely held corporation has “more than 50 per cent of the value of its outstanding stock owned (directly or indirectly) by five or fewer individuals at any time during the last half of the tax year”.
As Democratic leader of the US House of Representatives Nancy Pelosi noted, 90 per cent of US corporations meet this definition, including the giants Bechtel, Cargill, and Koch Industries.
East Montpelier, Vermont, US
Weedy story
I was concerned to read the diatribe against Japanese knotweed (5 July, p 38). While not wishing to defend some of knotweed’s thuggish habits, your article was in my view both biased and unscientific.
To describe it as having the “biodiversity value of concrete” is absurd. It is in fact a valuable nectar source for many insects, including honey bees.
Its phytochemistry is complex and fascinating and beyond the scope of this letter, but suffice it to say it has broad antibacterial, antifungal and antiviral activity as well as being a rich source of resveratrol, a compound claimed to have many health benefits.
The plant has a long history of use in Japan as a medicine and a food source. Was this article intended to be a PR stunt for the knotweed-munching psyllids, I wonder?
Lostwithiel, Cornwall, UK
Drug delivery
You describe a technique to use genetically tweaked red blood cells to deliver drugs that would otherwise break down after a few hours in circulation (5 July, p 14).
What is unclear is why this should be so. If the drugs in question decay so quickly, this would surely not change, given that the red blood cells are surrounded by blood, where decomposition would still occur.
Is it the case that the red cells would be expected to reach target organs faster than unattached drugs in the bloodstream?
What is the mechanism that might protect drugs being carried by red blood cells?
Glen Waverley, Melbourne, Australia
Drug delivery
鈥� For small-molecule drugs, excretion via the kidneys is the most common path of “decay”. If such drugs were attached to red blood cells, they would not be filtered out by the kidneys and so would persist for longer in the body.
For drugs in the form of antibodies and other proteins, removal via the kidneys is much slower, but there are enzymes in the circulation and in the liver that will degrade these molecules. While attached to red blood cells, they are hidden from these enzymes, extending their circulatory half-life.
Intelligent life
Nick Bostrom repeats the central transhumanist fallacy that there exists a mechanical shortcut to superior intelligence (5 July, p 26).
He claims three such shortcuts; via speed, collectivity and quality. All three are guaranteed to fail.
Fast processing does not guarantee superior intelligence. A fool given a million subjective years to write a program will write a million foolish programs.
Collective processing does not guarantee superior intelligence. For proof of this, study history.
Qualitatively superior programming would guarantee superior intelligence, if only we were intelligent enough to write it. But by definition we cannot think up programs superior to our own best thinking.
Thus our smartest programs, on the fastest machines in the biggest networks, must inevitably display not artificial intelligence but artificial stupidity. This machine’s stupidity will be as superhuman as its intelligence.
Alas, our cybernetic offspring must evolve by variation and natural selection, just like the rest of us.
San Francisco, California, US
Intelligent life
In common with many others, Bostrom assumes that top of the agenda for a superior artificial intelligence (AI) would be creating ever more capable successors without limit.
The cynic in me suggests that a sufficiently smart AI might, unlike us, be wise enough not to create its own replacement.
Of course, an AI so intelligent might also deduce that keeping around a modestly smart animal with a propensity for creating more artificial intelligences could be a threat to its survival, so this still doesn’t improve the prospects for us humans.
Waterford, Virginia, US
Ignoble gases
If Toby Pereira thinks xenon and argon are used by athletes as inert gases to simulate altitude training, he might wonder why nitrogen, a vastly cheaper alternative, is not used instead (12 July, p 26).
In fact, these noble gases are believed to have a biological effect related to the production of the performance-enhancing substance erythropoietin (EPO), so it is not absurd to classify them as “drugs”.
Prestwood, Buckinghamshire, UK
Font of life
Your article on searching for the origins of life in billion-year-old water samples was interesting (5 July, p 8), but the statement that “as far as the team could tell, the water contained no trace of life” is suspect.
One thing we should have learned from the search for life on other worlds 鈥� particularly the Mars Viking lander missions 鈥� is the extraordinary difficulty in developing instruments that are sensitive enough to detect biological activity.
And then there’s the extraordinary difficulty in persuading sceptical biologists that any findings are valid.
There is no mention in the article of what methods were employed to detect life in the Kidd Creek Mine water. Hopefully, this crucial detail will appear when the authors publish their results.
Poquoson, Virginia, US
Thunderbirds are go
When I saw the picture of the newly designed FireFly rocket, I couldn’t help thinking that I’d seen it before (12 July, p 5). Indeed I had. It was permanently ingrained on my memory way back in the 1960s when, as an impressionable young boy, I was completely besotted with anything to do with rockets and space.
I’m sure the scene in the image you printed is directly from the children’s TV series Fireball XL5, or indeed any of the many space-based B-movies from that era.
Rochdale, Lancashire, UK
For the record
鈥� The designer of the Hong Kong subway’s AI system is Andy Chun (5 July, p 17).
鈥� A lack of Curiosity: the Mars lander pictured in our book review was not the titular spacecraft (5 July, p 45).