Showing posts with label artificial intelligence. Show all posts
Showing posts with label artificial intelligence. Show all posts

Saturday, 26 January 2013

A Singular Thesis

The information revolution has brought our planet to an inflexion point. This is our generation's industrial revolution, and conventional wisdom of all sorts is suddenly in doubt. But is the universe really about to wake up? Are we about to look into the face of God? Ray Kurzweil thinks so.


Julian Jaynes rounds out his wonderful The Origins of Consciousness in the Breakdown of the Bicameral Mind with a sanguine remark that the idea of science is rooted in the same impulse that drives religion: the desire for “the Final Answer, the One Truth, the Single Cause”.

Nowhere is this impulse better illustrated, or the scientific mien so resemblant of a religious one, than in Ray Kurzweil’s hymn to forthcoming technology, The Singularity Is Near. For if ever a man were committed overtly - fervently, even - to such a unitary belief, it is Ray Kurzweil. And the sceptics among our number could hardly have asked for a better example of the pitfalls, or ironies, of such an intellectual fundamentalism: one one hand, this sort of essentialism features prominently in the currently voguish denouncements of the place of religion in contemporary affairs, often being claimed as a knock-out blow to the spiritual disposition. On the other, it is too strikingly similar in its own disposition to be anything of the sort. Ray Kurzweil is every inch the millenarian, only dressed in a lab-coat and not a habit.

Kurzweil believes that the “exponentially accelerating” “advance” of technology has us well on the way to a technological and intellectual utopia/dystopia (this sort of beauty being, though Kurzweil might deny it, decidedly in the eye of the beholder) where computer science will converge on and ultimately transcend biology and, in doing so, will transport human consciousness into something quite literally cosmic. This convergence he terms the “singularity”, a point at which he expects with startling certainty that the universe will “wake up”, and many immutable limitations of our current sorry existence (including, he seems to say, the very laws of physics) will simply fall away.

Some, your correspondent included, might wonder whether, this being the alternative, our present existence is all that sorry in the first place.

But not Raymond Kurzweil. This author seems to be genuinely excited about a prospect which sounds rather desolate, bordering on the apocalyptic, in those aspects where it manages to transcend sounding simply absurd. Which isn’t often. One thing you could not accuse Ray Kurzweil of is a lack of pluck; but there’s a fine line between bravado and foolhardiness which, in his enthusiasm, he may have crossed.

His approach to evolution is a good example. He talks frequently and modishly of the algorithmic nature of evolution, but then makes observations not quite out of the playbook, such as: “the key to an evolutionary algorithm ... is defining the problem. ... in biological evolution the overall problem has always been to survive” and “evolution increases order, which may or may not increase complexity”.

Kurzweil seems to be genuinely excited about a prospect which sounds rather desolate, bordering on the apocalyptic, wherever it manages to transcend sounding simply absurd. Which isn’t often.
But to suppose an evolutionary algorithm has “a problem it is trying to solve” - in other words, a design principle - is to emasculate its very power, namely the facility of explaining how a sophisticated phenomenon comes about *without* a design principle. Evolution works because organisms (or genes) have a capacity - not an intent - to replicate themselves. Nor, necessarily, does evolution increase order. It will tend to increase complexity, because the evolutionary algorithm, having no insight, is unable to “perceive” the structural improvements implied in a design simplification. Evolution has no way of rationalising design except by fiat. The adaptation required to replace an overly elaborate design with more effective but simpler one is, to use Richard Dawkins’ expression, an implausible step back down “Mount Improbable”. That’s generally not how evolutionary processes work: over-engineering is legion in nature; economy of design isn’t, really.

This sounds like a picky point, but it gets to the nub of Kurzweil’s outlook, which is to assume that technology evolves like biological organisms do - that a laser printer, for example, is a direct evolutionary descendent of the printing press. This, I think, is to superimpose a convenient narrative over a process that is not directly analogous: a laser printer is no more a descendent of a printing press than a mammal is a descendent of a dinosaur. Successor, perhaps; descendant, no. But the “exponential increase in progress” arguments that Kurzweil repeatedly espouses depend for their validity on this distinction.

The “evolutionary process” from woodblock printing to the Gutenberg press, to lithography, to hot metal typing, to photo-typesetting, to the ink jet printer (thanks, Wikipedia!) involves what Kurzweil would call “paradigm shifts” but which a biologist might call extinctions; each new technology arrives, supplements and (usually) obliterates the existing ones, not just by doing the same job more effectively, but - and this is critical - by opening up new vistas and possibilities altogether that weren’t even conceived of in the earlier technology - sometimes even at the cost of a certain flexibility inherent in the older technology. That is, development is constantly forking off in un-envisaged, unexpected directions. This plays havoc with Kurzweil’s loopy idea of a perfect, upwardly arcing parabola of utopian progress.

It is what I call “perspective chauvinism” to judge former technologies by the standards and parameters set by the prevailing orthodoxy - being that of the new technology. Judged by such an arbitrary standard older technologies will, by degrees, necessarily seem more and more primitive and useless. The fallacious process of judging former technologies by subsequently imposed criteria is, in my view, the source of many of Ray Kurzweil’s inevitably impressive charts of exponential progress. It isn’t that we are progressing ever more quickly onward, but the place whence we have come falls exponentially further away as our technology meanders, like a perpetually deflating balloon, through design space. Our rate of progress doesn’t change; our discarded technologies simply seem more and more irrelevant through time.

Evolutionary development is constantly forking off in unexpected directions. This plays havoc with Kurzweil’s loopy idea of a perfect, upwardly arcing parabola of utopian progress.
Kurzweil may argue that the rate of change in technology has increased, and that may be true - but I dare say a similar thing happened at the time of the agricultural revolution and again in the industrial revolution - we got from Stephenson’s rocket to the diesel locomotive within 75 years; in the subsequent 97 years the train’s evolution been somewhat more sedate. Eventually, the “S” curves Kurzweil mentions flatten out. They clearly aren’t exponential, and pretending that an exponential parabola might emerge from a conveniently concatenated series of “S” curves seems credulous to the point of disingenuity. This extrapolation into a single “parabola of best fit” has heavy resonances of the planetary “epicycle”, a famously desperate attempt of Ptolemaic astronomers to fit “misbehaving” data into what Copernicans would ultimately convince the world was a fundamentally broken model.

If this is right, then Kurzweil’s corollary assumption - that there is a technological nirvana to which we’re ever more quickly headed - commits the inverse fallacy of supposing the questions we will ask in the future - when the universe “wakes up”, as he puts it - will be exactly the ones we anticipate now. History would say this is a naïve, parochial, chauvinistic and false assumption.

And that, I think, is the nub of it. One feels somewhat uneasy so disdainfully pooh-poohing a theory put together with such enthusiasm and such an energetic presentation of data (and to be sure, buried in Kurzweil’s breathless prose is plenty of learning about technology which, if even half-way right, is fascinating), but that seems to be it. I suppose I am fortified by the nearby predictions made just seven years ago, seeming not to have come anything like true just yet:

“By the end of this decade [i.e., by 2010] computers will disappear as distinct physical objects, with displays built in our eyeglasses and electronics woven into our clothing”

On the other hand I could find scant reference to “cloud computing” or equivalent phenomena like the Berkeley Open Infrastructure for Network Computing project which spawned schemes like SETI@home in Kurzweil’s book. Now here is a rapidly evolving technological phenotype, for sure: hooking up thousands of serially processing computers into a massive parallel network, giving processing power way beyond any technology currently envisioned. It may be that this adaptation means we simply don’t need to incur the mental challenge of molecular transistors and so on, since there must, at some point, be an absolute limit to miniaturisation, as we approach it the marginal utility of developing the necessary technology will swan dive just as the marginal cost ascends to the heavens; whereas the parallel network involves none of those limitations. You can always hook up yet another computer, and every one will increase performance.

I suppose it’s easy to be smug as I type on my decidedly physical computer, showing no signs of being superseded with VR Goggles just yet and we’re already three years into the new decade (he also missed the mobile computing revolution, come to think of it), but the point is that the evolutionary process is notoriously bad at making predictions (until, that is, the results are in), being path-dependent as it is. 


You can’t predict for developments that haven’t yet happened. Kurzweil glosses over this shortfall at his theory’s cost. 

A version of this article was first published on Amazon in 2010.

Friday, 3 February 2012

The End – or the Start – of Ignorance

 
E.O. Wilson is just the latest biologist to try turning the base metal of scientific induction into the spun gold of existential truth. What is the allure of religious certainty for these folks, and why they can’t heed the lessons of their own discipline?


I’ve made  the observation before that scientists - especially biologists - make lousy philosophers, and it doesn’t take long for Professor E. O. Wilson - one of evolutionary biology’s most prominent lights - to place himself squarely in that camp.

“No one should suppose,” he asserts, “that objective truth is impossible to attain, even when the most committed philosophers urge us to acknowledge that incapacity. In particular it is too early for scientists, the foot soldiers of epistemology, to yield ground so vital to their mission. ... No intellectual vision is more important and daunting than that of objective truth based on scientific understanding.”

On the other hand not long afterwards, apparently without intending the irony with which the statement overflows, he says, “People are innate romantics, they desperately need myth and dogma.”

None more so, it would seem, that philosophising evolutionary biologists. 

Wilson’s Consilience is a long essay on objective truth that - per the above quotation, gratuitously misunderstands what epistemology even is, whilst at the same time failing to mention (except in passing) any of its most important contributors - the likes of Wittgenstein, Kuhn, Quine, Rorty or even dear old Popper. Instead, Wilson characterises objections to his extreme reductionism as “leftist” thought including - and I quote - “Afrocentrism, ‘critical’ (i.e., socialist) science, deep ecology, ecofeminism, Lacanian psychoanalysis, Latourian sociology of science and neo-Marxism.”

Ad hominem derision is about the level of engagement you’ll get, and the only concession - a self-styled “salute” to the postmodernists - is “their ideas are like sparks from firework explosions that travel away in all directions, devoid of following energy, soon to wink out in the dimensionless dark. Yet a few will endure long enough to cast light on unexpected subjects.” You could formulate a more patronising disposition, I suppose, but it would take some work.

“You could formulate a more patronising disposition, I suppose, but it would take some work.”

What is extraordinary is that of all scientists, a biologist should be so insensitive to the contingency of knowledge, as this is the exact lesson evolutionary theory teaches: it’s not the perfect solution that survives, but the most effective. There is no “ideal organism”.

In support of his own case, Wilson refers at some length to the chimerical nature of consciousness (taking Daniel Dennett’s not uncontroversial account more or less as read). But there is a direct analogy here: Dennett’s model of consciousness stands in the same relation to the material brain as Wilson’s consilience stands to the physical universe. Dennett says consciousness is an illusion - a trick of the mind, if you like (and rather wilfully double-parks the difficult question “a trick on whom?”).

But by extension, could not consilience also be a trick of the mind? Things look like they’re ordered, consistent and universal because that’s how we’re wired to see them. Our evolutionary development (fully contingent and path-dependent, as even Wilson would agree) has built a sensory apparatus which filters the information in the world in a way which is ever-more effective.  That’s the clever trick of evolutionary development. If it is of adaptive benefit to apprehend “the world” as a consistent, coherent whole, then as long as that coherent whole accounts effectively for our physiologically meaningful experiences, then its relation to “the truth” is really beside the point.

When I run to catch a cricket ball on the boundary no part of my brain solves differential equations to catch it (I don’t have nearly enough information to do that), and no immutable, unseen cosmic machine calculates those equations to plot its trajectory either. Our mathematical model is a clever proxy, and we shouldn’t be blinded by its elegance or apparent accuracy (though, in point of fact, practically it isn’t that accurate) into assuming it somehow reveals an ineffable truth. This isn’t a new or especially controversial objection, by the way: this was one of David Hume’s main insights - an Enlightenment piece of enlightenment, if you will. As a matter of logic, there must be alternate ways of describing the same phenomena, and if you allow yourself to implement different rules to solve the puzzle, the set of coherent alternative solutions is infinite.

“It is extraordinary that a biologist should be so insensitive to the contingency of knowledge, it being the exact lesson of evolutionary theory.” 

So our self-congratulation at the cleverness of the model we have arrived at (and, sure, it is very clever) shouldn’t be overdone. It isn’t the “truth” - it’s an effective proxy, and there is a world of difference between the two. And there are uncomfortable consequences of taking the apparently harmless step of conflating them.

For one thing, “consilience” tends to dissuade inquiry: if we believe we have settled on an ineffable truth, then further discussion can only confuse and endanger our grip on it. It also gives us immutable grounds for arbitrating against those who hold an “incorrect” view. That is, to hold forth a theory which is inconsistent with the mainstream “consiliated” view is wasteful and given it has the potential to lead us away from the “true” path, may legitimately be suppressed.

You can see this style of reasoning being employed by two groups already: militant religious fundamentalists, and militant atheists. Neither is prepared to countenance the pluralistic, pragmatic (and blindingly obvious) view that there are not just many different *ways* of looking at the world but many different *reasons* for doing so, and each has its own satisfaction criteria. While these opposing fundamentalists go hammer and tongs against each other, their similarities are greater than their differences, and their greatest similarity is that neither fully comprehends, and as a consequence neither takes seriously, the challenge of the “postmodern” strands of thought against which they’re aligned.

Hence, someone like Wilson can have the hubris to say things like: “Yet I think it is fair to say that enough is known to justify confidence in the principle of universal rational consilience across all the natural sciences”

Try telling that to Kurt Gödel or Bertrand Russell, let alone Richard Rorty or Jacques Derrida.

Friday, 20 January 2012

Vanquishing magic by sleight of hand

Douglas Hofstadter’s essay on the incompleteness of loopy logical systems starts out brightly, but makes a disappointing and strangely unimaginative resort to reductionism in the end. Pity.
Philosophy, to those who are disdainful of it, is a sucker for a priori sleights of hand: purely logical arguments which do not rely for grip on empirical reality, but purport to explain it all the same: chestnuts like “cogito ergo sum”, from which Descartes concluded a necessary distinction between a non-material soul and the rest of the world.

Douglas Hofstadter is not a philosopher (though he’s friends with one), and in I am a Strange Loop he is mightily disdainful of the discipline and its weakness for cute logical constructions. All of metaphysics is so much bunk, says Hofstadter, and he sets out to demonstrate this using the power of mathematics and in particular the fashionable power of Gödel’s incompleteness theory.

Observers may pause and reflect on an irony at once: Hofstadter’s method - derived a priori from the pure logical structure of mathematics - looks suspiciously like those tricksy metaphysical musings on which he heaps derision. As his book proceeds this irony only sharpens.

But I’m getting ahead of myself, for I started out enjoying this book immensely. Until about halfway I thought I’d award it five stars - but then found it increasingly unconvincing and glib, notably at the point where Hofstadter leaves his (absolutely fascinating) mathematical theorising behind and begins applying it. He believes that from purely logical contortion one may derive a coherent account of consciousness (a purely physical phenomenon) robust enough to bat away any philosophical objections, dualist or otherwise.

Note, with another irony, his industry here: to express the physical parameters of a material thing - a brain - in terms of purely non-material apparatus (a conceptual language). In the early stages, Professor Hofstadter brushes aside reductionist objections to his scheme which is, by definition, an emergent property of, and therefore unobservable in, the interactions of specific nerves and neurons. Yet late in his book he is at great pains to say that that same material thing cannot, by dint of the laws of physics, be pushed around by a non material thing (being a soul), and that configurations of electrons correspond directly to particular conscious states in what seems a rigorously deterministic way (Hofstadter brusquely dismisses conjectures that your red might not be the same as mine). Without warning, in his closing pages, Hofstadter seems to declare himself a behaviourist. Given the excellent and enlightening work of his early chapters, this comes as a surprise and a disappointment to say the least.

Hofstadter’s exposition of Gödel’s theory is excellent and its application in the idea of the “Strange Loop” is fascinating. He spends much of the opening chapters grounding this odd notion, which he says is the key to understanding consciousness as a non-mystical, non-dualistic, scientifically respectable and physically explicable phenomenon. His insight is to root consciousness not in the physical manifestation of the brain, but in the patterns and symbols represented within it. This, I think, is all he needs to establish to win his primary argument, namely that Artificial Intelligence is a valid proposition. But he is obliged to go on because, like Darwin’s Dangerous Idea, the Strange Loop threatens to operate like a universal acid and cut through many cherished and well-established ideas. Alas, some of these ideas seem to be ones Douglas Hofstadter is not quite ready to let go. Scientific realism, for example.

The implication of the Strange Loop, which I don’t think Hofstadter denies, is that a string of symbols, provided it is sufficiently complex (and “loopy”) can be a substrate for a consciousness. That is a Neat Idea (though I’m not persuaded it’s correct: Hofstadter’s support for it is only conceptual, and involves little more than hand-waving and appeals to open-mindedness.
“Perhaps, rather than slamming the door on mysticism, Hofstadter has unwittingly blown it wide open. After all, why stop at human consciousness as a complex system?” 
But all the same, some strange loops began to occur to me here. Perhaps rather than slamming the door on mysticism, Douglas Hofstadter has unwittingly blown it wide open. After all, why stop at human consciousness as a complex system? Conceptually, perhaps, one might be able to construct a string of symbols representing God. Would it even need a substrate? Might the fact that it is conceptually possible mean that God therefore exists?

I am being mendacious, I confess. But herein lie the dangers (or irritations) of tricksy a priori contortions. However, Professor Hofstadter shouldn’t complain: he started it.

Less provocatively, perhaps a community of interacting individuals, like a city - after all, a more complex system than a single one, QED - might also be conscious. Perhaps there are all sorts of consciousnesses which we can’t see precisely because they emerge at a more abstract level than the one we occupy.

This might seem far-fetched, but the leap of faith it requires isn’t materially bigger than the one Hofstadter explicitly requires us to make. He sees the power of Gödel’s insight being that symbolic systems of sufficient complexity (“languages” to you and me) can operate on multiple levels, and if they can be made to reference themselves, the scope for endless fractalising feedback loops is infinite. The same door that opens the way to consciousness seems to let all sorts of less appealing apparitions into the room: God, higher levels of consciousness and sentient pieces of paper bootstrap themselves into existence also.

This seems to be a Strange Loop Too Far, and as a result we find Hofstadter ultimately embracing the reductionism of which he was initially so dismissive, veering violently towards determinism and concluding with a behavioural flourish that there is no consciousness, no free will, and no alternative way of experiencing red. Ultimately he asserts a binary option: unacceptable dualism with all the fairies, spirits, spooks and logical lacunae it implies, or a pretty brutal form of determinist materialism.

There’s yet another irony in all this, for he has repeatedly scorned Bertrand Russell’s failure to see the implications of his own formal language, while apparently making a comparable failure to understand the implications of his own model. Strange Loops allow - guarantee, in fact - multiple meanings via analogy and metaphors, and provide no means of adjudicating between them. They vitiate the idea of transcendental truth which Hofstadter seems suddenly so keen on. The option isn’t binary at all: rather, it’s a silly question.

In essence, all interpretations are metaphorical; even the “literal” ones. Neuroscience, with all its gluons, neurons and so on, is just one more metaphor which we might use to understand an aspect of our world. It will tell us much about the brain, but very little about consciousness, seeing as the two operate on quite different levels of abstraction.

To the extent, therefore, that Douglas Hofstadter concludes that the self is that is an illusion his is a wholly useless conclusion. As he acknowledges, “we” are doomed to “see” the world in terms of “selves”; an a priori sleight-of-hand, no matter how cleverly constructed, which tells us that we’re wrong about that (and that we’re not actually here at all!) does us no good at all. Neurons, gluons and strange loops have their place - in many places this is a fascinating book, after all - but they won’t give us any purchase on this debate.