Letters archive

You say that "climate change is, emphatically, not a political issue" (Leader , 27 April ). While agreeing with everything else you wrote, I must disagree with this. We humans have devised numerous economic models by which to conduct our affairs. They can be divided between two broad headings: market forces and planning for need. …

In view of your exemplary recent coverage on the depth and urgency of the climate crisis, I was shocked by your dismissive comments on the recent Extinction Rebellion protests. To put the record straight: 1130 supporters were arrested, with many, many thousands on the streets, and the protests were entirely peaceful and respectful. The protests …

David Hambling reports a proposal that auroral sounds come from corona discharges at an altitude of less than 100 metres ( 6 April, p 40 ). In the 90s, I was at Esrange Space Center, near Kiruna in the north of Sweden. One quiet, wind-free night, I heard an aurora. I told some scientists from …

Watching people, in particular young children, concentrating on using their hands for a fine motor skill while sticking out their tongue lends credence to the possibility that language began with hand movements ( 4 May, p 34 ). I wonder whether speech developed as our ancestors began to live in groups, with some members going …

Since gathering, rather than hunting, provided the majority of calories for early communities, why is such a focus for the origins of language placed on suggestions of what may have aided our ancestors to hunt, rather than to gather? Some propose singing for protection as the origin of language. Maybe this started when the gatherers …

You report that DeepMind's artificial intelligence was unable to add up seven 1s, and that it concluded that 17 × 4 is 69 ( 13 April, p 12 ). That is artificial stupidity. Until now, artificial stupidity was the responsibility of the human programmers. Now, the machine is stupid on its own. I predict that …

Tom Stafford argues that the idea that free will doesn't exist is based on misguided intuitions of what it means to be a biological machine ( 6 April, p 34 ). Is it fair to assume that any scientific model of the mechanism of a free will decision should ultimately be expressible in mathematical form? …

Stafford confuses complexity with freedom. He admits that "our thoughts are caused by our brains, our environment and our history". But he maintains that, because this causal mix is unique to each individual at each moment, human behaviour is so difficult to predict that it is elevated above that of digger wasps. Yet so long …

Discussing whether cystic fibrosis carriers might recognise each other, Richard Harris says "it seems extremely unlikely that one mutated gene among tens of thousands would be detectable by smell" Letters, ( 20 April ). But there are examples of just this. For example, trimethylaminuria, also known as fish odour syndrome, is caused by a mutation …

Alongside Daniel Cossins's interesting article on fast radio bursts, you describe the comparative magnetic field strengths of various bodies, but sadly use the antiquated non-SI unit, the gauss ( 11 May, p 34 ). The tesla is the modern SI unit of magnetic flux density. You showed a comparison of the field strength of commercial …