Self and sensibility
In his forthcoming book, Julian Baggini (12 March, p 34) will probably address the fact that we each at different times experience our “self” as first person singular 鈥� “I”, as first person plural 鈥� “we”, and even as second, or sometimes third, person. And the first person is experienced differently in different tenses: I think, therefore I was; I feel, therefore I am; I ought, therefore I shall be.
As for free will, aren’t scientists applying it when they decide that something is true, and write an article about their findings, and that something else is false, and say so? What would “truth” be, if we are not “free” to recognise it?
From Ernest Ager
Baggini must be using a different definition of “discover” to the one I use. In reference to the ponderings of the philosopher David Hume that each of us is merely a bundle of thoughts, sensations and experiences (a belief also held by the Buddha) he says that “neuroscience confirms and explains the mechanics of this centreless self, but it certainly didn’t discover it”.
Many people have hypotheses, thoughts and guesses; they ponder upon them and even believe them. This is not discovery. In the late 1400s, people hypothesised about lands to the west of the Atlantic; do we therefore strip Columbus of his “discovery” of America?
Baggini says he does not wish to disparage neuroscience, yet says “it is simply a philosophical mistake” to think that understanding more about the nuts and bolts of the basis of self and identity must add something to fundamental understanding of what makes us the individuals we are. But until we carry out the experiments, we are “merely” guessing at the nature of selfhood 鈥� even if our guesses are very well thought out and based on observation of the human condition. Any or all of these ideas may be mistaken.
Neuroscience 鈥� science 鈥� allows us to discount some of the ideas, and to build on the remainder. It makes discoveries.
Exmouth, Devon, UK
From Ella Taylor-Smith
Apart from a passing reference to the environment a person finds themself in, Baggini’s discussion of self seems limited to the individual’s internal experience. However, self is also an external construct, legally and socially.Our behaviours are strongly influenced (even circumscribed) by the expectations of other people 鈥� family, colleagues, friends and partners.
Perhaps the next step in exploring self is to gauge the relative influence of internal and external factors or even to question whether an individual’s conception of their self is always more valid than someone else’s.
Edinburgh, UK
From Bob Humphrey
The existence of a “delay-line” between the unconscious part of the brain deciding to move, for example, and you or I becoming consciously aware of this does not necessarily imply any lack of free will. It is quite possible that the unconscious part is “me” and undertakes my thought processes including making decisions; and these are all passed to the “display” part of the brain to form conscious awareness, albeit after a short delay. This would not mean these decisions were anything other than real and “mine”.
Bristol, UK
Wrong trousers
How refreshing to see Richard Bergman suggesting an alternative to the body mass index (BMI) of obesity, which makes muscular men anxious (12 March, p 31). Back in the 1970s my colleagues and I discovered that there was a weirdly accurate correlation between the incidence of coronary disease in the UK and the ratio of waist to inside-leg length of trousers sold by a well-known drapery store.
I could not persuade the big trouser company to part with the raw sales data, so we could not publish in a journal. But we had seen the heart and trouser maps, and we spread the news at lectures in the hope of un-spreading waistlines.
From Frank Hollis
When I saw this item was about somebody questioning BMI as a measure of obesity I thought “at last!” But I was surprised to find that its most obvious flaw was not mentioned. Indeed, I’ve never seen it mentioned. Why does the BMI assume that one’s weight should be proportional to the square of one’s height, when it should obviously be proportional to the cube of height, that is to one’s volume, for an optimum body density?
Steyning, West Sussex, UK
The editor writes:
鈥� A tall person who was a scaled-up short person could be very big-boned indeed: so the mass divided by the cube of height (the “Ponderal index”, apparently) is wrong too. BMI is a workable approximation.
Expanding Earth
Over the past 20 years we seem to be getting a double whammy of disasters 鈥� the climate-related alongside an apparent increase in the frequency and severity of earthquakes. Are they linked?
There is debate over whether glaciers melting and releasing pressure on the Earth’s crust contribute to earthquakes.
Another factor in their frequency could be the expansion of the Earth’s crust as it warms. The atmosphere has warmed by around 0.8 掳C over the last century, and the oceans by somewhat less. This warming will affect the thermal gradient of the lithosphere and we could well be starting to see the effects of this.
Simple calculations show that if a 1000-kilometre-long sheet of rock is heated by 0.5 掳C per century, then this translates into an expansion of around 2.7 centimetres per year in basalt and 4.3 in granite. This is the same order of magnitude as the movement of the tectonic plates that triggers earthquakes.
The editor writes:
鈥t seems to take a very long time for temperatures changes to permeate a significant thickness of the crust: so probably not yet.
Never grow old
So what makes humans different from our nearest relatives is that we have lost some regulatory DNA (12 March, p 3 and p 6) which controls how genes are expressed. This may help revive a century-old theory.
Louis Bolk, and later Gavin De Beer, Desmond Morris and Stephen Jay Gould, observed that human beings have more in common with infant chimpanzees than with their adult parents. We have managed to work out the function of two of the 510 chunks of DNA that we have lost and they seem to allow juvenile development (brain growth in this case) to continue longer than it was “meant” to. If the other 508 have similar functions it looks as though the neoteny theory has fared very well indeed.
Ape ancestors growing like an infant for much longer by losing regulatory DNA makes sense as a theory for the origin of humanity.
Perhaps we will have to change the name of our species to Peter Pan troglodytes– the chimp that never grew up.
Regeneration blues
Colin Barras described a connection between unicellular animals and cancer cells, which suggests that cancers may lie at the origin of the animal kingdom (12 March, p 12).
Fifty years ago, I came across the suggestion that the rapid proliferation of undifferentiated cells that a lizard needs to grow a replacement tail was similar to the growth of a tumour. Presumably a network of blood vessels develops in the new tail, as it does in some tumours, which would add weight to the idea.
We may not need to go back to our single-cell state to find a relationship with tumvours; just to when we were reptiles.
Pitching in again
Absolute pitch is not “the secret of musical genius” as your cover proclaims (26 February). Real music in natural settings is concerned with relative, not absolute, pitch.
Your mates in the pub start belting out Roll out the Barrel beginning with and ending on any old pitch, and you’re expected to sing along successfully. Your choir tires in performance and sinks, so you end up in a slightly sharp E major instead of the original F. On the other hand, your orchestra plays sharper as the instruments warm up, so you approach a flat F sharp in the finale. Or you’re a pianist accompanying a singer who says “I’m out of sorts today; let’s lower the next song a semitone”. That’s real music.
And composers couldn’t care less about absolute pitch. Their work is to create a soundscape in which tones only have meaning in relation to other tones. How long until someone tells us that great authors are sensitive to the absolute sounds of letters?
Homecoming cat
Roger Highfield’s observation that the return journey feels faster than the outward (19 February, p 34) might also apply to animals. Our (rather overweight) cat likes to follow us on our occasional night walks along the river near our home. Once we leave his familiar territory he indicates his increasing distress, as his pitiful miaows become louder and more frequent the further away from home we travel.
As we approach our regular turnaround point he generally sits down to await our return journey, during which he makes no noise at all, and even rests from time to time, being well aware that this is the way home. We have observed a similar pattern of vocalisations on trips to and from the vet, despite the fact that he is in his cat box the whole time.
Maybe he has a built-in homing device.
Bait switch
Is SUSY dead or missing as your headline asked (19 March, p 10)? Nah, she’s not coming to the party until those with what you dub “baited breath” use a good mouthwash. Presumably they’re using a Large Halitosis Collider? We wait with bated breath for her arrival.
The editor writes:
鈥ur shame is unabated.
For the record
鈥� We described nematode researcher Cori Bargmann as a “he” 鈥� our apologies to her (19 March, p 21).
鈥� Astrobiotic, creator of the Red Rover, is no longer partnered with the Raytheon corporation (5 March, p 46).