Letters archive

Fred Pearce reports how lawsuits over climate change might bring justice along the lines of "polluter pays" ( 18 August, p 38 ). But from where might the payee raise the fines? From taxes or from energy charges, no doubt. There is thus a risk of sending money in circles, unless the fines are all …

Being wrong should be on the curriculum: what holds people back is fear of it Kate Shaw MA, MS, PsyD responds to a report that we can train ourselves to better know when we are wrong ( 1 September, p 14 ) .

• Paul Jackson was not involved with the refurbishment of the bridge that collapsed in Genoa ( 25 August, p 4 ).

Clare Wilson and Andy Coghlan cover many of the possible explanations for the decrease in the improvement of life expectancy in the UK ( 25 August, p 20 ). But they miss one out. The effect is historically far more noticeable in the poor than the wealthy. There is a measurable gradient of difference across …

Who's testing our thoughts to see how well we understand them? Dave Probert responds to our report that AIs are being tested to see how well they understand our thoughts ( 8 September, p 10 )

You report that an "opt-out" system for organ donation could reduce transplant rates, as relatives are less confident their late family member agreed and so may be more likely to veto donation ( 25 August, p 16 ). I have always wondered why families are permitted to veto an individual's decision about organ donation. They …

Sally Adee mentions work on more secure computer hardware carried out by Ruby Lee and Howie Shrobe ( 11 August, p 36 ). From the late 1970s, the late Roger Needham and others, including Bjarne Stroustrup , who went on to design the C++ programming language, worked on the CAP computer , which embodied a …

I agree with Ian Adam in finding Stephen Harris's claims regarding foxes killing cats unconvincing (Letters, 18 August ). If a fox had "weak jaws", why would it chew off, and then remove, the head (which it presumably could not then eat), rather than going for the "soft underbelly" where the internal organs would be …

Douglas Heaven suggests five commandments for robots ( 4 August, p 38 ). I agree with the last commandment, that a robot should have an off switch, but I think the others need more work. For example, the first prevents a robot from allowing a human to come to harm "unless it is supervised by …

• Actual allergy to gluten does exist , but is very rare ( 11 August, p 28 ). • In a nuclear reactor, a moderator slows neutrons after they are released ( 1 September, p 32 ). • A study finds that eukaryotic cells first appeared between 1.21 and 1.84 billion years ago ( 25 …