Thursday, February 14, 2008

Animal Wrongs, evolution and gravity

I left a rather breathless comment at Tim Worstall's blog recently, railing against factory farming of chickens, and didn't look back to see how the discussion developed.

I hate industrial livestock farming and buy free range poultry and pork, and wild meat wherever possible. That's not to say (straw man #1 in the comments that followed) that I want to ban it. There is a case for animal welfare legislation and therefore a debate about how far it should extend, but I'm instinctively against banning anything. I'd prefer it if people voted with their feet, hence the comment on a blog rather than a letter to my MP asking him to introduce new legislation.

Straw man #2 was that I should become a vegetarian. It's another post, but I think vegetarianism is immoral, or possibly amoral, though again I wouldn't ban it.

Then there was the predictable accusation of anthropomorphism. It's bizarre how some people seem to regard any gesture of recognition that animals can suffer as anthropomorphic. I have come to think of this attitude as "lithomorphism": the attribution of the characteristics of lumps of rock to higher animals with complex nervous systems and brains. Apart from anything else, it's stupid because it's counter-factual.

But the comment that really struck me was this one, from Philip Thomas, a science teacher, who wrote:

“For a century and a half, since Darwin, it has been intellectually and morally insupportable to uphold the religious belief, akin to creationism, that humans are qualitatively different to other species.”

By definition, humans are different from other species. Darwin pointed to all species being connected but not that we were some blurred continuum. Quite the opposite in fact.
He was quoting my earlier interjection, which an observant reader might have noticed said "since Darwin" and therefore included work done in the past century or so as well as that of the great man.

Humans are different from other species in the same way that lions are different from other species, in the latter case including humans. That doesn't do anything to distinguish humans in a unique way. But in fact species are part of "some blurred continuum", as the post-Darwin discovery of ring species has underlined. We're looking at a snapshot of a process, when we look at an animal. We call patterns in the variations between individual creatures "species" when they are sufficient to prevent interbreeding. When variations are even greater than just that we have other words, like genus. But that's just us, classifying things. We like to classify things but it's an imposition of order, not an underlying reality.

Richard Dawkins has coined a term for the widespread inability to see continua instead of discrete units - the "discontinuous mind":
We would all agree that a six-foot woman is tall, and a five-foot woman is not. Words like 'tall' and 'short' tempt us to force the world into qualitative classes, but this doesn't mean that the world really is discontinuously distributed. Were you to tell me that a woman is five feet nine inches tall, and ask me to decide whether she should therefore be called tall or not, I'd shrug and say 'She's five foot nine, doesn't that tell you what you need to know?' But the discontinuous mind, to caricature it a little, would go to court (probably at great expense) to decide whether the woman was tall or short. Indeed, I hardly need to say caricature. For years, South African courts have done a brisk trade adjudicating whether particular individuals of mixed parentage count as white, black or coloured.

The discontinuous mind is ubiquitous. It is especially influential when it afflicts lawyers and the religious (not only are all judges lawyers; a high proportion of politicians are too, and all politicians have to woo the religious vote). Recently, after giving a public lecture, I was cross-examined by a lawyer in the audience. He brought the full weight of his legal acumen to bear on a nice point of evolution. If species A evolves into a later species B, he reasoned closely, there must come a point when a mother belongs to the old species A and her child belongs to the new species B. Members of different species cannot interbreed with one another. I put it to you, he went on, that a child could hardly be so different from its parents that it could not interbreed with their kind. So, he wound up triumphantly, isn't this a fatal flaw in the theory of evolution?

But it is we that choose to divide animals up into discontinuous species.
This isn't an entirely abstract point. There is a continuing battle over whether or not creationism should be taught in school science lessons, or more broadly as a valid intellectual position rather than as a load of archaic and superstitious drivel of purely anthropological interest. One of the key arguments deployed in support of creationism is an argument from incredulity (it's a logical fallacy as well as ignorant) over the process of speciation. Animals can't just lurch suddenly in one generation between quite distinct species, it is argued. Well no, they can't, and nobody should suggest they do. We are looking, with our discontinuous minds, at a continuum and we like to classify the things we see in it, to sort them into groups and put each group in a pigeon hole. It's helpful in some ways to do that, no doubt, but it isn't the underlying reality, to repeat myself for emphasis.

There's another argument used by creationists, especially those who have dug up the corpse of William Palley, dressed it in fine new clothes and propped it up in a chair with a sign round its neck, saying "Intelligent Design": that creationism is a theory, and so is evolution. Most of the time this is criticised, it is on the basis that the word "theory" is being abused. The scientific meaning of the word "theory" is close to the everyday use of the word "fact" - it's an idea that has been tested, preferably extensively, and not yet disproved. The popular use of the word "theory" is closer to "not a fact". Creationism is "not a fact" whereas the idea of evolution by natural selection is a "fact". But there is something in science even closer to a "Fact", and that's a phenomenon.

Take gravity as an example. There's a phenomenon: apples fall on people's heads. That's a fact. Newton thought they did so because masses attract, and that was a theory. It wasn't right, but it worked and so took a long time to disprove. Then Einstein suggested that mass affects space, which in turn affects other masses. This explained the effect of mass on something like light, which Newton's theory failed to do. But there's no completely acceptable theory of gravity yet, not least because anything that seems to work and can be tested properly is hard to reconcile with other parts of physical theory.

So we have a phenomenon - falling apples - and we have theories that seek to explain it, like quantum gravity and string theory. It's worth noting in passing how very long it took before anyone noticed that even such an obvious and ubiquitous thing as gravity was a phenomenon that needed an explanation. People just took it for granted, like the (equally unnoticed, for such a long time) air they breathed.

Applying this system of classification (there we go again) to biology, evolution itself isn't a theory, it's a phenomenon. Like gravity, it took a long time for people to notice it, perhaps in part because noticing it would have led, for many centuries, to a fiery death. That this phenomenon is caused by natural selection is a theory, and it's such a good one that it is still not disproved. This makes it equivalent to the use, in everyday language, of the word "fact", but it isn't quite a fact - it's a well tested and consistently successful scientific theory.

Religious refusal to accept the existence of a phenomenon - an actual observable thing - is not unusual. After all, there were longstanding religious objections to the existence of gravity, as Galileo discovered to his cost. An acceptance of the existence of gravity as a measurable physical phenomenon leads inexorably to the realisation that the observed phenomena of the motion of planets means the sun is at the centre of the solar system. That doesn't rely on any particular theory of gravity, just on the observed behaviour of objects.

Perhaps one of the most serious claims that can be levelled against religions is that they make clever people think incredibly stupid things and even deny the existence of incontrovertible physical phenomena like gravity and evolution.

But it isn't just religion that can do this. To a lesser degree, chauvinism makes people stupid, and specism is just as stupid as racism. And that's where we came in.

UPDATE: Just for clarification, specism is the division of the world's fauna into the two categories of humans, and everything else. Thus, a trout is lumped together with a cow, whereas a chimpanzee is separated from a human, when the question of ethical treatment is considered.

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