Wednesday, 31 December 2008

White Crows, Black Swans, Half-and-Half Sheep


I want to end the year with a favourite joke, and by telling you about a project from this year that did not work out (or, let's be optimistic, has not yet worked out). The joke is related to the project and, somehow, embodies something I want to explore. It goes like this:

Four scientists -- a mathematician, a physicist, a biologist and an astronomer -- go on a trip to Scotland. As they cross the border, they see a black sheep in a field.

"Amazing!" says the astronomer, "All the sheep in Scotland are black!"


"Don't be silly," says the biologist, "It would be more precise to say that some sheep in Scotland are black."


"Nonsense," says the physicist, "You need to be much more precise than that: all we can say with certainty is that in Scotland at least one sheep is black!"


The mathematician sighs. "You people make me laugh with your sloppy talk about precision... I think the best we can say is that there is one field in Scotland containing one sheep, one half of which is black."
Now, this joke does not make everybody laugh, and this may be my problem. Indeed, if the mathematician's "one half of which" does not make you laugh (or at least raise a wry smile) then I am clearly barking up the wrong tree (or simply barking). Perhaps, like me, you need to have spent more time than is healthy or normal writing and debugging Perl programs and Unix shell scripts to see the point of the joke.

So. We all know that a black sheep is black all over, and that the idea of a sheep bilaterally divided between black and, well, some other unknown colour (hey, let's not jump to conclusions -- it could be purple) is ludicrous. Don't we? Just as we all knew that the sun went round the earth until, of course, some idiot with a mathematical bent proved otherwise, simply by (a) making the observations, (b) doing the maths, and (c) mentally keeping open the possibility that, so to speak, one half of the sheep might not be black.



But that's the interesting thing about many jokes: we can laugh at "the other," but in the process, part of the other's "other-ness" gets assimilated. Racist jokes do not exist, I am sure, in societies that are not in the process of becoming multi-racial. (On the other hand, I probably wouldn't counsel a programmatic barrage of racist jokes as a means of accelerating the process ...)

But what interests me is (c) above -- we may not have the time, inclination or ability to do (a) and (b), but being open to the possibility that things may not be what they seem is something we can all aspire to. Mind you, it's still quite a rare trait. Even people who would lay claim to open-mindedness can be intolerant of inconvenient truths. Try explaining to an academic who has made the political-economic judgement that, say, Microsoft is a Bad Thing, that nonetheless the reason their PowerPoint presentation doesn't work is because, simply, they have failed to take account of how PowerPoint actually works -- it is unconnected with any alleged evil being worked by Bill Gates in the world [still haven't worked out how to spell that evil laugh ... "Bwahahahaha"?].

Simply seeing what's in front of you is quite a skill, and usually has to be learned (or rather, certain perceptual shortcuts have to be unlearned). It's a large part of becoming a half-decent photographer. Have you ever taken this Awareness Test? It's quite well known now, but most people feel considerably humbled (and amused) by their first encounter with it.

But back to my project. This year, the book The Black Swan : the impact of the highly improbable by Nassim Nicholas Taleb was widely reviewed and discussed. Its central thesis is neither highly original nor hard to summarise: indeed, the book's subtitle does a good job. However, the ramifications of this simple idea (that the unpredictable, highly unlikely event is precisely the one likely to have the most impact) and its corollary (that we may be rather too dependent on the predictions of "experts" who are little more than astrologers in suits) are many. Look no further than the current economic crisis. But, quite how anyone would make the world a better place by trying to anticipate the highly improbable is hard to see. And do I feel the draught from a back door being opened for Superstition to sneak into the House of Reason?




But, setting aside thoughts of Douglas Adams' "improbability drive," you can see how the mathematician in the joke has got something right by leaving the door open to the unknown in the very precision of his method. The "black swan" is a traditional problem in philosophy, usually associated with Carl Popper and his view that falsifiability is an essential characteristic of a scientific theory. But this is dull stuff for a New Year's Eve: there's a good discussion of that here. It boils down to the fact that the observation of a single black swan is sufficient to falsify the proposition "All swans are white." But there is a more intriguing real-life example, and one which seems to push open that draughty back door even wider.

Towards the end of the 19th century, William James (philosopher brother of literary windbag Henry James) became convinced of the supernatural powers of Leonora Piper, a trance medium. In an address to the Society for Psychical Research in 1890, he said: "If you wish to upset the law that all crows are black, you mustn't seek to prove that no crows are; it is enough to prove one single crow to be white." He believed Leonora Piper to be his white crow. In other words, even if all other mediums were shown to be fraudulent, her example showed that mediumship was a true possibility. Maybe so: but as the sceptical psychologist James McKeen Cattell responded in 1896, "One white crow is enough, but its skin should be deposited in a museum."

So, a heady mix: a basic tenet of scientific method, a trance medium, open minds and closed minds, improbable things, "always" versus "sometimes", etc. But above all, crows. I like all the crows: rooks, jackdaws, magpies, ravens, they're all magic to me. I know a lot of people don't like them. But I love the way the rooks see off the buzzards and sparrow-hawks that circle over our street; I'm intrigued by the magpie parliaments that convene in the trees behind our house with much hissing, clicking and squawking; I'm amazed by the intelligence of the typical crow, ducking and diving around the ragged edges of the human world; I'm in awe of the huge mixed flock of crow species that gathers at dusk on winter evenings over the fields before settling for the night in their traditional trees.




One of my Christmas presents this year was the Rat Hole Press reprint of Masahisa Fukase's Solitude of Ravens, one of the great photobooks, and a fine example of how to bring many concerns together in a photographic sequence. But can I put all this together myself in a satisfactory way? Not yet... Maybe next year.

My best wishes to anyone reading this for a happy, peaceful and fulfilling year in 2009.

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