Belief elsewhere

Letters– Neurons mirror what? From Richard Kennaway, School of Computing Sciences, University of East Anglia A. C. Grayling’s essay (3 May, p 50), with its leap in argument from diffuse flashes of neuron activity to universal morality, is a series of non sequiturs. Whether one performs an action, or observes someone else doing it, there is a perception of that action. Is there any reason to conclude that the neurons activated in both cases are doing anything more than that? The leap to assigning to them the “seat of empathy” is frequently made, but I have yet to see it justified. Even if that were so, what would it tell us? We already know that people can read other people’s intentions. The crudity of existing brain measurements allows us only to find the

approximate location of what might be the brain “hardware” running a process. This tells us nothing about what it might be capable of. It is fanciful to describe these gross measurements as “direct insight into other people’s states of mind”. (A colleague likens the process to UFO hunters seeing flashes of light in the sky and exclaiming “Ooh! There’s an alien spaceship!”) What is the connection with morality? There is a suggested connection with autism, but autistic people are not especially known for their failure of moral behaviour; whereas intelligent psychopaths can be perfectly competent at social interaction. 20 | NewScientist | 24 May 2008

And even if “fundamental morality” is to be found in the neurons, where other than in the neurons does Grayling expect to find the “customs” that differ between cultures? The whole thesis is thus a tautology. Norwich, UK From Matt Hollingsbee When A. C. Grayling suggests that empathy induced by mirror neuron activity is “the very basis of social capacity itself, and thus of morality” and that therefore “moral judgement is hard-wired – and therefore universal”, he ignores the fact that empathic responses are themselves subject to personal and cultural bias. Treating others as you would like to be treated yourself falls down because others do not necessarily want to be treated in the same way as you might like to be treated yourself. One can easily imagine a culture where people go through some ceremony which we find disgusting or cruel, firing off all manner of mirror neurons in our brains, only to discover that for the participants it was the proudest day of their lives. Reading, Berkshire, UK From Catherine Scott Thanks to A. C. Grayling for once again demonstrating to us the profound silliness of biological reductionism. We have neurons in our brains that fire when we see people performing actions or reacting to circumstances, so that means there is only one way of defining the good life? Oh, come on! Beyond some basic situations, what pleases or distresses you is a matter of meaning, not biology. Meaning is bestowed on actions and experiences by culture. Camberwell, Victoria, Australia

Short cuts in mind From Paul Mealing You report John-Dylan Haynes finding it possible to detect a decision to press a button up to 7 seconds before subjects are aware of deciding to do so (19 April, p 14).

Haynes then concludes: “I think it says there is no free will.” In the same issue Michael Reilly interviews Jill Bolte Taylor, who says she “was consciously choosing and rebuilding my brain to be what I wanted it to be” while recovering from a stroke affecting her cerebral cortex (p 42). Taylor obviously believes she was executing free will. The brain is very good at delegating tasks to the subconscious to make them effectively automatic. A good example is walking: we never consciously think about taking a step, as we did when learning to walk. If we did, we wouldn’t be able to walk and talk at the same time. We do it with language as well: writing this, I don’t have to consciously place every word. If free will is an illusion, Taylor’s experience suggests that the brain can subconsciously rewire itself while giving us the illusion that it was our decision to make it do so. There comes a point where the illusion makes less sense than the reality. Melbourne, Australia

results by asking different questions. That’s why we used a shortened version of a table originally published in Science.

Coley’s cure From William Hughes-Games Using bacteria to treat cancer is hardly unexpected (29 March, p 17). In the 1890s, William Coley effected many cures using mixed killed cultures of Streptococcus pyogenes and Serratia marcescens. The critical factor was the induction and maintaining of a fever. Tumours typically disappeared completely in under a month (12 January, p 34 and 2 November 2002, p 54). Coley also observed that fevers induced by such diverse diseases as influenza, measles, malaria and smallpox caused malignant tumours to disappear. The difference with the modern use of Listeria monocytogenes is that it has been genetically modified and hence can be patented. Coley’s toxins cost at most a few dollars per cure. Waipara, New Zealand

Belief elsewhere From Sally John Michael Le Page reported rates of belief in evolution from 18 countries (19 April, p 31). The opinions of residents of Iceland, Latvia and Denmark are reported, while China, India, Brazil, South Africa, Canada and Australia are left out. One country in Asia (Japan) and one country in North America (US) are included, but not a single country in Africa or South America is mentioned. There’s a whole opinionated and intelligent world out there. Salt Spring Island, British Columbia, Canada The editor writes: ● If anybody has done large-scale polls in these countries, we couldn’t find them. Even if they were done, it is difficult to compare results of different polls as you can get quite different

Carbon to go From Richard Symes I am a farmer, and I would love to grow trees for Ning Zeng (3 May, p 32). He can reduce the wood to carbon and then bury it. There are lots of empty ships going back to China, and he could use these to transport the carbon and bury it in empty Chinese coal mines. As fast as he can bury his “new coal” others will be digging coal out from the other end to burn in China’s power stations: so we will never run out of space. Until he gets this organised, I will continue with my age-old practice of heating my house by burning the wood in a stove. Halesworth, Suffolk, UK From Chris McCoy What on Earth, quite literally, are people thinking of? Burying half www.newscientist.com