Not as we know us
Douglas Heaven suggests that modern artificial intelligence is a form of intelligence we have never encountered before (10 August, p 32). I suggest that we may well have done so 鈥� every time we meet a fellow human. We don’t know how our intelligence works, and it is plausible that it works in exactly the same way as the AI described.
Heaven worries about trusting AIs that make predictions without being able to provide a logic to justify them. But every day psychiatrists and other expert witnesses advise courts based on their professional experience, without being able to provide exact algorithmic reasons for their statements.
Newbury, Berkshire, UK
Not as we know us
Is it not possible that we in fact think like our robots? We think we take logical steps in observing that cats are carnivores, carnivores eat meat, therefore cats eat meat. But aren’t these mere statistical associations? Philosopher David Hume argued similarly in the 18th century.
London, UK
Not as we know us
Our brains are fed vast amounts of information through our senses, much as AIs are fed information from the internet. Our subconscious brain must process and filter this and relate it to prior input 鈥� as AIs do for Google or Amazon. It then deposits usable output into our conscious mind as “news headlines” which register as the thoughts, insights and ideas we need to run our lives and survive, procreate and progress.
Bath, Avon, UK
Not as we know us
You describe statistical methods generating unexplainable, but interesting, results. I have encountered some inexplicable results myself: after ordering Jared Diamond’s book about social collapse I was told that I would also be interested in the autobiography of a footballer called Wayne Rooney.
I don’t much mind people (or machines) believing I am a fan of Wayne Rooney.
My worry is that security agencies use similar systems to spot suspicious behaviour, and might conclude that an interest in a book on social collapse indicated a predisposition to treason.
That could prove fatal.
Harrogate, North Yorkshire, UK
Modest alien search
From Alan Penny, UK
Your report on the UK SETI Research Network was a bit overenthusiastic (13 July, p 6). This informal network was formed to promote UK academic activity in the search for extraterrestrial intelligence through meetings and possible collaborations. Our discussions have not yet produced an actual proposal for a search.
Any such proposal will probably be modest. Our members are open to all sources of funding, private and public, and indeed three of us have previously made (unsuccessful) applications for funding to private foundations.
The figure of 拢1 million a year that you mention was merely my personal estimate of what would, in the long term, be a justifiable total level of UK SETI activity 鈥� some 0.5 per cent of the UK astronomy budget.
St Andrews, Fife, UK
Keeping time
Anil Ananthaswamy wonders whether space, time, both or neither form the basis of reality (15 June, p 34). Worryingly, he points out that one candidate for a theory of everything, loop quantum gravity, indicates that time and space are emergent entities of a deeper reality rather than fundamental elements.
Here’s hoping for an approach that keeps time as fundamental. A plausible theory of everything that allows Achilles finally to overtake the tortoise and Zeno’s arrow finally to fly, 2500 years after these paradoxes were posed in Greece, will let some of us go to our rest untroubled by fears of an eternity of Groundhog days.
Dublin, Ireland
Many wrongs?
Reality, relativity, causality and free will. You ask “which one is wrong?” (3 August, p 32). It might have been better to say “at least one of them is wrong”. At a minimum, our understanding of both reality and causality is hindered by a long-standing mental block in interpretations of quantum mechanics, namely the bad habit of according a special place to “measurement”.
Neither “measurement” nor its evil twin “instantaneous collapse” corresponds to anything real in quantum equations, where all interactions are equally quantum and wave forms only evolve, not collapse. They were only ever intended by the pioneers of QM as placeholders to acknowledge our incomplete understanding of how the classical world arises from underlying quantum interactions.
If I had to take a guess, it would be that the most fundamental reality is conservation of information, and that the quantum/classical transition reflects the transition from the fully reversible, information-preserving world of quantum mechanics to the irreversible world of thermodynamics and entropy. This transitional domain might be probed with practical and thought experiments.
Waterford, Virginia, US
<i>From Wilken Sporys</i>
Who is to say our understanding of any of them is right? Certainly, relativity tells us that time and space are not quite as we perceive them. Any object travelling at the speed of light will arrive at the same instant that it left, without travelling any distance at all. Time and space only emerge as an object or particle slows below the speed of light. Yet to us time and space seem indisputably real.
Christmas Hills, Victoria, Australia
Mars bars
Articles about colonising Mars continue to gloss over the temperature and composition of its atmosphere (13 July, p 42). It seems disingenuous to act as though people can actually discuss living out a significant part of their lives in spacesuits and pressurised hulls. There is no precedent; even extended submarine patrols and International Space Station tours are not years long.
Springfield, Virginia, US
Mars bars
You mention that “one of the mooted Martian settlement projects has proposed funding the trip using a reality TV show” (27 July, p 5).
Will there be evictions?
Great Missenden, Buckinghamshire, UK
Glutamate booster
Glutamate, the king of neurotransmitters, provides the primary means whereby brain cells communicate. As so clearly discussed by Samantha Murphy (27 July, p 34), it is also a likely but elusive culprit in depression.
Beyond the cumbersome general anaesthetic ketamine, means to manipulate glutamate pathways are few. The system remains inaccessible to conventional antidepressant action. Curiously, however, it seems that n-acetylcysteine, an “antioxidant” safely used in the treatment of lung disease and sold as an over-the-counter supplement, vigorously modulates glutamate activity in synapses between neurons.
Even if it does not directly relieve depression, n-acetylcysteine may at least increase the action of existing antidepressants. I hope that such exciting but preliminary claims will be validated.
Rochester, Minnesota, US
Open access fields
Feedback is concerned about open access publishing, noting that “someone has to pay… [often] the researcher, whose livelihood depends on being published somewhere” (27 July). This may well apply to the commercial and academic science sectors.
It does not apply in the substantial sector serviced by museums and “volunteers” in the “poor” areas of biodiversity, taxonomy and conservation. Our peer-reviewed journals predate others by centuries and our writers are either unpaid, or employees of poorly funded institutions. Open access publication to us means not having to pay to read background material for unpaid work. Our work is accessed freely by commerce and academe: it’s time they responded in kind.
Anstey, Leicestershire, UK
Obey the odds
Tim Johnson suggests that we can “move the odds a bit in favour of free will” by positing that, as happens with events in the quantum world, our human behaviour is not just subject to the scientific laws of causality but is also subject to the laws of probability (13 July, p 32).
Whether I am obeying probability or causality, or both, I am still not free.
Lancaster, UK
Picnic of fear
Your article on the influence of fear on prey species and the consequent ecological impacts of their resulting behaviour was fascinating (1 June, p 36). A few years ago I visited a waterfall in Shimba Hills National Reserve, Kenya, with a family group.
We walked down to the waterfall in an excited garrulous group as if on a picnic in a London park. Once the excitement of playing Tarzan in the plunge pool had worn off, however, our thoughts turned to elephants, which are common in the park, potentially dangerous and surprisingly hard to spot in scrub and light forest. On the walk back we saw fresh elephant dung: we moved cautiously and completely silently, with scouts out.
Unlike the elk of Yellowstone National Park, our strategy was to keep out of the woods, preferring clear lines of sight. Does this lend support to the evolutionary value of our upright stature?
New Delhi, India
Needs must
I noticed that two recent readers’ letters referred to the saying “Necessity is the mother of invention” (20 July, p 28, and 3 August, p 30). In an age when we are so dependent on smartphones and other gadgets, perhaps this should be amended to: “Invention is the mother of necessity.”
New York, US
For the record
鈥� To refer to the “eradication” of river blindness in Colombia (10 August, p 6) was overambitious: its removal from just one region is “elimination”
鈥� We should have made it clear that software analysis of DNA from the scene of the murder of Meredith Kercher indicated only that Amanda Knox’s DNA was not present in one sample on a bra clasp found at the crime scene (6 July, p 15)