Editor's pick: What can cause tipping points in perception of risk?
You observe that the history of humanity is one of stupidity, denial and dawdling followed by heroic rearguard action (Leader, 13 October). I read this on the day that the firm Cuadrilla was allowed by our wretched establishment to resume fracking. My thoughts turned to the point perhaps 30 or 40 years ago when there was what seems in hindsight to have been a sudden sea change in thinking about tobacco and cancer.
In my youth, the argument could be summarised as the tobacco companies asserting there was no “scientific proof” that smoking caused cancer, while the scientific community waffled on about determinism versus probabilism and stochastic versus non-stochastic understanding of phenomena. The scientists conceded that, strictly in terms of ideal levels of statistical significance for their findings, it was difficult to counter the claim that causation was “not proven” and so on.
Then, quite abruptly and universally, it did not seem to matter any more that the gold standard 5-sigma level of statistical significance hadn't been achieved. People appeared to accept the link, and it was now difficult to find anyone but the most diehard tobacco company shareholder who would disagree with the assertion.
So what was it that caused the perception switch? Was it a matter of persistently hammering on until it penetrated even the thickest of skulls, or was there some crucial argument that swayed everyone?
If there was a key influence and we could determine what it was, that would be extraordinarily helpful. I note that Donald Trump has acknowledged that the climate is changing, although he remains to be convinced that this is due to human actions. Who knows, perhaps this will prove to be a tipping point equivalent to the one for tobacco over a generation ago.
The obstacles that Emmy Noether faced
You criticise Alessandro Strumia's unacceptable and biologically false comments on the abilities of female physicists (Leader, 6 October). His views highlight an appalling, continuing basal sexism that dogs the physical sciences as it does other fields.
But to compare Emmy Noether's difficulty in getting a university position with Albert Einstein's life is perhaps not good history. He too had problems. Graduating , he repeatedly failed to get a position. He took a job as a private tutor, before personal connections got him , Switzerland. Even after the 1905 publication of the papers that changed modern physics, including his Nobel-prizewinning explanation of the photoelectric effect, he waited three years to get .
The brilliant Noether gained her doctorate in 1907, but before she got a paid university position. Like Einstein, she had an additional profound “burden” in the nationalistic pit that was then Germany: she was a Jew.
First class post 鈥� 10 November 2018
As long as they don't have to deal with humans
Ann Morgan that orangutans are exceptionally good at keeping their infants alive (3 November, p 8)
'Folk economic' beliefs are not so stupid (1)
Pascal Boyer highlights the idea that “wealth is a fixed-size pie” as an example of economic folklore (22 September, p 40). But the counterposition to which most economists subscribe – that greater inequality is a price worth paying for most people being generally better off – is no more based in fact.
The philosopher John Rawls explores this argument at length in . He asks you to assume you don't know your position in the social order, and then choose between a society in which a small pie is shared more equally, or a larger pie more unequally but with the average person better off.
Most, of course, will go for the latter option. But framing the question this way ignores the fact that greater inequality actually makes the pie smaller. When social groups have different interests, an elite group will make decisions that preserve the privilege of its members rather than benefiting everyone.
Nobel laureate economist Joseph Stiglitz makes precisely this argument in . “Folk economics” does include a fundamental truth, honed over millennia of biological and cultural evolution. Group cohesion born of fundamental equality encourages decisions that ensure group survival. We would be foolish to dismiss it.
'Folk economic' beliefs are not so stupid (2)
Pascal Boyer says economics is “not an exact science”. The study and practice of economics is not science at all. No notion espoused by an economist of whatever leaning has had any greater predictive power than a chimp trying to choose a winning horse at the Grand National.
The fact that most economic “theories” assume limitless inputs and outputs – raw materials and waste to the rest of us – may go some way to explaining how hopelessly unrealistic the field is.
Self-awareness may be a very primitive need
Sofia Deleniv discusses challenges to the notion that self-awareness is a higher form of consciousness (8 September, p 28). It seems to me that it is merely a result of having a multicellular body.
Consider an early animal with chemical, optical and mechanical sensor cells spread around its simple body. It already needs a way to filter the signals from those cells, to concentrate its attention only on what is relevant at that moment. Animals lacking this would go extinct.
In you, this filter would be a neural mechanism that would allow you to distinguish yourself from your environment and have an idea about what is happening inside – are you hungry, scared, in the mood for a mate? It allows animals to focus their attention on a subset of sensory inputs, and could be the bud of our self-awareness and consciousness.
What is the true climate impact of electric cars?
Roy Harrison is correct when he states that an electric car has a similar carbon dioxide impact to a petrol-powered hybrid car if the batteries are charged from a gas-fired power station with a carbon footprint of 400 grams per kilowatt-hour (Letters, 6 October). But this is almost never the case.
The UK generation mix now includes a lot of renewables, meaning the average carbon footprint fell from 531g/kWh in 2012 to less than 300g/kWh in 2017. It continues to fall as the use of renewables increases and coal power stations close. See it in real time at .
The result is that an electric car in the UK produces less CO2 than any petrol-powered hybrid.
Surely we'd have evolved not to need to fast
The idea of regular fasting to make you healthier (20 October, p 30) seems to be based on the idea that humans evolved on what is now called a Paleo diet, periodically going without food for days at a time. But humans have adapted within a few centuries to be more tolerant of milk (13 October, p 10), alcohol (6 February 2010, p 17) and Western diets (23 July 1994, p 14).
Although regular fasting may be beneficial for some, I suggest most of us may benefit more from adaptations that we have evolved over the past 10,000 years, as a result of living with an agricultural system that provides reasonable food supplies all year.
Reinforced concrete is a clever composite too
Faced with the problem of greater brittleness being associated with increased strength, nature tackles it by rearranging internal microstructures, as Liz Kalaugher points out (29 September, p 40). We see the same phenomenon in ceramics – and in that ubiquitous material, concrete.
Also emulating nature, we often reinforce material with bundles of fibres. The resulting composite has both enhanced strength and toughness compared with the original material alone.
Yes, we have no meat coupons this week
At its recent conference in Incheon, South Korea, the Intergovernmental Panel on Climate Change called for a reduction in meat-eating to help reduce global warming.
In turn, William Nordhaus, the freshly elevated Nobel laureate in economics, recommended that households should pay a price on their carbon emissions, some of which indirectly result from eating meat (13 October, p 4).
Both objectives could be met if meat were subject to a voucher system. Give everyone coupons regardless of their requirements, and adjust the quota according to temperature-control targets.
This would mirror the system already in place for international carbon credits, which are tradable. Vegetarians could sell their coupons to meat-eaters. Butchers might find employment as meat-voucher traders. Such a system might also help to regenerate the community spirit that existed during and briefly after the second world war.
Take heed of a warning from the goddess Dawn
So one in five want immortality (22 September, p 8). Perhaps they need to study the Greek myth of Tithonus. His goddess lover Dawn persuaded Zeus to grant him immortality, but . Loathsome old age pressed full upon him, he could not move nor lift his limbs, and babbled incessantly.
In later versions, Tithonus pleads to leave the human world and is changed into a cricket – still begging for death.
For the record 鈥� 10 November 2018
• Cholesterol is a lipid that animals use to build cell membranes (29 September, p 12).
• On a long fuse: satellites with manipulators could be used to defuse an opponent's orbiting bomb (24 October 1968, p 176).
• Sponges' spicules are made of silica (20 October, p 8).