The programming talent myth

I wrote it and then thought 'oh crap, this is both offtopic and pointless rambling and also teaching Neil to suck eggs'. Nice to see I was being excessively paranoid!

> We still have vestigial instinct such as fight-or-flight.

I'm firmly of the believe that 'instinct' is a nearly meaningless category. All our neurons are placed into their final resting places by a feedback loop between genes and cellular microenvironment: many of them also include a feedback loop between cell and *external* environment (including those involved in things you'd think didn't, such as vision). Mammals have almost protean developmental pathways. Some of the behaviours encoded by those neurons are not very variable after they are established (e.g. heartbeat regulation). Others are more variable. It's a continuous gradation, not a division into enumerable "instincts" and "everything else". Elephants have to learn how to use their trunks with delicacy from other elephants: does that mean it's not an instinct? Even if it does, that surely doesn't mean we could learn to do the same thing!

> Is the knowledge of a 2 year old nature or nurture? Doubtlessly both.

The division is meaningless. The neural architecture of an unborn child six months in the womb is both nature and nurture (the neurons don't develop without environmental input, some internally generated and some from things like sound leaking through the womb wall). The architecture of a week-from-conception female child is both nature and nurture (which X is inactivated in which cell? What DNA methylation patterns are established? Hugely significant for all of future development, and more or less random with some environmental influence.)

Asking 'nature or nurture' is like saying 'this computer has really good hardware! Therefore its software must be pathetic, because its hardware does everything.' In reality, having more hardware often means the software too must be more complex: in biology, being a more complex organism often means that your relationship with your environment, and the regulatory networks it controls, just get more complex. We are a long way from getting to the bottom of this. Hell, in the last few years entire new *classes* of regulatory network have been uncovered...

Clearly some things (e.g. your knowledge of your mother's name) are strongly environmentally influenced, but even they will be the result of environment acting on neurons, changing their gene expression, and feeding back. When all of memory is like this, and so are most things that aren't memory, 'nature or nurture' really means very little. The most you can ask is 'is this behaviour variable across the population, and does it vary widely in closely related individuals' -- but that doesn't mean it's 'nurture not nature', it means it's nature with complex environmental responses.

> 2/ But we *did* do those things. We (humanity, not you and me personally) built the tools that perform the calculations. Our brains are so versatile, they allow us to do things that our brains cannot do themselves.

In that case it's impossible to ask whether there are things we cannot learn: if we encounter such a thing, we'll never know it's even there since we cannot learn of its existence. Therefore you have taken the question of the range of human mental capacity outside the realm of science.

It is still clear that we can't learn *anything*: there are lots of unsolved questions in mathematics that we don't know the answer to because we have no way to work it out, or because working it out is intractable. Much of the last century of science (computer science in particular) has been the story of the discovery of new limits: I strongly suspect that such limits exist in the human mind as well, simply because there is no reason for evolution to have selected for a universal thinking machine when something simpler and likely less energy-hungry would do (energy expenditure and heat dissipation are *major* constraints on human evolution, and the brain is a huge energy suck). Why would a generalist hunter/gatherer/scavenger on the African savannah evolve a brain capable of literally anything?

(It is definitely clear that in the domain of language we do a lot via metaphors and the like, often frozen into customary forms by centuries of use to such a degree that we don't even recognise them as metaphors any more. To me, this says that we *do* have cognitive limits, but that language at least sometimes helps us end-run around them. Even there, we can't handle everything: there are a lot of not especially complex grammatically valid linguistic structures that we just can't parse because of apparent arbitrary limits. A universal thinking machine would not have a limit of at most three on the number of centre-embeddings it could handle!)

> Processing incoming sensory information, finding patterns, and patterns in patterns, and pattern in patterns in patterns. This is fundamental to how we think and learn and it starts very early.

Except we *can't do that* for anything but language, and we can't do that conciously. We find patterns, yes, but in a conscious, linear fashion: we can't listen to a massive blur of sound and do all this extraction work without thinking about it except when a very young child in the critical language-learning window. This is hardwired behaviour -- or, in the form I describe above, neurons predetermined to respond to environmental input (usually auditory) by doing this massive set of pattern-matches.

> I wonder what exactly you mean by "linguistic processing". Earlier you seemed to differentiate mathematics from language. If your definition of "linguistic processing" maintains that differentiation, that I think there is much more to how I, at least, think and the practical value that I get from my brain than just "linguistic processing".
> Even if you do include mathematics, there is the whole realm of "subconscious thought" which doesn't seem in any way linguistic yet still brings value to the individual and the species.

Mathematics has language as a prerequisite, if you will: its foundation is the concept of a number line which is not only geometric but has numbers spaced regularly along it. Those numbers are linguistic entities, and in languages spoken by cultures with advanced mathematics are recursive combinatorial entities obeying a grammar (you can build a word for any number you like). Whether mathematics has *other* prerequisites is hard to say: no other animal has this prerequisite, and as far as we know no other animal has anything like the field of mathematics. (As opposed to, say, the sort of unconscious stuff you do when catching a ball, which is mathematics *implemented by neurons* rather than mathematics you think about. Almost everything alive has that sort of mathematics encoded in it somewhere, even bacteria, but that doesn't mean they can do mathematics in the sense we mean here.)

> A question for philosophers: can a blind person learn to recognize "blue"?
> Obviously they never will, but would their brain be able if the sensory input was there?

This has been tested in people blind from birth due to cataracts: yes they can, but they don't seem to have good outcomes due to just not being able to handle the flood of visual information as easily as we can: they can see, but it's difficult to make sense of the scene as a whole and they get overwhelmed very easily. It seems likely that a lot of the visual cortex either hasn't developed properly in such people, has been excessively trimmed due to inactivity or has been repurposed for auditory purposes (very common in blind people, as well as deaf people the other way: early parts of the auditory and visual signal processing pathways use very similar algorithms and very similar patterns of neural organization, so are easy to repurpose).

Again here we see the faultiness of the term 'instinct'. Visual processing is a vastly complex pile of neural machinery carrying out at least hundreds and quite possibly thousands of distinct tasks, with all sorts of environmental feedbacks in its development (from autogenerated test patterns on the retina in the womb, through to matching of corresponding points on the retinae of both eyes for stereo-vision development in a critical window in infancy, and doubtless more that is not yet known). It is reused by all sorts of things you might not expect to use it (e.g. remembering a visual scene and visual imagination both feed into the visual cortex 'backwards', and you can even guess at what's being imagined if you spy on the right parts of the cortex; if your visual cortex is lost, you can no longer remember what colours are or what things looked like). Things that were believed to be largely hardwired, like synaesthesia, have recently been discovered to be environmentally influenced: some people with colour/letter synaesthesia have colour/letter correspondences matching those in a particular Fisher-Price plastic letter set. Even conscious thought ripples down into the early visual cortex down feedback loops: this has been tested with the Necker cube, where you can lean to flip your perception of the cube by thinking about it, and when you do about 10% of the neurons in the earliest regions of the visual cortex flip with it.

So, is vision an instinct, given that a lot of it is hardwired? Is it thousands of instincts? Is it learned, given that you can easily break quite a lot of it through environmental deprivation, that things like synaesthesia are influenced by the colours of plastic letter sets, and that conscious thought can directly affect the activity of neurons in even the most fundamental parts of the visual cortex? It is both. It is neither. It is more complex than that. (This is biology. *Everything* is "more complex than that". There's a reason a lot of old-time hackers have gone into biology now -- it satisfies their desire for crazy levels of complexity! :) )