Letters archive

Michael Graziano says we might be able to begin to develop artificial visual consciousness with existing technology, but that it will take a lot longer to build a machine with a stream of consciousness ( 21 September, p 34 ). I have a sneaking suspicion that we will develop an artificial human-like brain before we …

The idea of an "attention schema" as a "self-reflecting mirror" that is the brain's representation of how the brain represents things, so that consciousness isn't so much an illusion as a self-caricature, is beguiling and probably correct. But Graziano is mistaken in suggesting that he knows how to solve "the hard problem" of consciousness. The …

I welcome Graziano's statement at the beginning of his article that "instead of trying to grapple with the hard problem" of consciousness, he takes "a more down-to-earth approach". But he then discusses an attention schema and sensory and verbal capabilities. All he is really entitled to claim is that a machine having these would be …

Graziano's article on consciousness was enlightening, especially the proposal to build a machine that reflects the author's consciousness model and see whether it displays conscious behaviour. My question is: how would you know whether it was or wasn't conscious? We have difficulty determining whether a human in a coma or with locked-in syndrome is conscious. …

Brazil is burning its forests to make room for farms ( 28 September, p 12 ). Canada and the UK have already cleared vast tracts of forest for the same purpose, which is why the situation in Brazil is so critical globally. Instead of vilifying developing nations, we should either pay them to maintain their …

Graham Lawton describes the oft-repeated "fact" that we have 11 years to save the planet as "a subtle misrepresentation of the science" ( 12 October, p 22 ). Other misrepresentations are less subtle. For example, Extinction Rebellion co-founder Roger Hallam claimed on the BBC HARDtalk programme in August that "science predicts" that 6 billion people …

Digging up coal may well be a "strange decision" for a country such as Botswana that has vast solar resources, as Joeri Rogelj at the International Institute for Applied Systems Analysis in Austria says ( 5 October, p 7 ). But we should also be concerned by countries such as Greece, which also has vast …

The failure to give developing countries an incentive to transform their energy systems is a major stumbling block to meeting the targets of the Paris climate agreement. Renewable technology is ready for deployment in countries such as Botswana .

Research into the effects of electric fields on plant growth has resumed in China ( 24 August, p 42 ). A number of years ago, we owned an old summer house in Charlevoix, east of Quebec city. An activity that we enjoyed there was picking the wild blueberries that were abundant not too far away. …

In his interview with Richard Dawkins, Graham Lawton refers to the idea in evolutionary biology that human brains are naturally receptive to religious ideas ( 21 September, p 38 ). I am not sure we need an evolutionary explanation for religious belief. Like many animals, we can see patterns and relations in geography, time and …