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Monday, 30 March 2009

Everything you know is wrong

Have you ever woken up, stretched, and before you had time to stop yourself, suddenly realised that everything you know is wrong?

Probably not.

Most people never have that happen to them, even if they really are wrong about everything.

I lived in South Africa during the apartheid years, and you’d think that no White South Africans supported the system to hear people talk now – but believe me, as an opponent of the system, I didn’t get much support. At some stage a lot of people must have changed their opinions, some without missing a beat or changing their perception of facts they had available for years.

If their views today are correct, they must have applied a very different filter to reality in the past.

This mysterious ability to interpret events in the light of a preconception, with an unshaken belief that any new facts that contradict that belief can’t be correct, has a name. It’s called confirmation bias.

Confirmation bias is the tendency to discount facts that don’t fit your preconception.

Let’s look at another example, one of my favourite examples: climate change.

I am going to look at just one aspect of this by now stale debate: the argument that it was much warmer than today during Mediaeval times. There’s an extensive bunch of web pages devoted to this cause, collecting a mass of evidence showing that talk of it being unusually warm today is some sort of conspiracy. The trouble is, they didn’t bother to line up all the dates and average the temperatures world-wide, which is what you look for if you are looking for global climate change. If it was unusually warm in one spot 1000 years ago, unusually warm somewhere else 500 years ago, unusually warm in yet another spot 1500 years ago, you don’t have a global warm period. Yes, there is evidence that parts of the world were warmer then. No one disputes that. But if you look at isolated temperature records, you can find all sorts of apparent anomalies. Layer those over a preconception, and you have a “theory” – but not one you can call science.

If you are already convinced of the case, the mass of evidence papers over the cracks pretty well. But I am a sceptic. I want to analyze any theory put to me for flaws, and a mass of evidence that’s not tied together properly does not make a case. The fact that no one has put that evidence together and yet the authors of the site in question claim they do already have a case should convince no one but those who want to be convinced irrespective of the facts.

So am I guilty of confirmation bias?

Nothing would please me more than to discover that the whole global warming thing was a hoax. We know from experience of other clashes between industry interests and campaigns for the common good that industry wins – or at least can resist for decades (tobacco, asbestos, the ozone hole).

If the mainstream opinion of climate science is correct (or even too optimistic, as some argue), we are in deep, deep trouble, because there is no way we will be able to take sufficient action in time to avoid significant ill effects. So I am really keen – despite having run for the Greens a couple of times – to find flaws in the theory. The problem is, every attempt I’ve seen to do so is heavily larded with confirmation bias. We see use of language like “alarmist” that’s designed to appeal to those already convinced: to me a sure sign of lack of confidence in the argument (why appeal to the emotions if your logic is sound?). We see harping on points that have been debunked. We see doubtful statistical methodology, attempts at interpreting data without any scientific method (naturally while claiming to be “real science” – this is the language of propagandists, not scientists), we see nitpicking insignificant points that do nothing to overturn the basics of the science.

In short, I’m waiting to be convinced. I would be really happy to wake up one day to discover that everything I know about climate change is wrong. What about the people pushing the contrary case? Are they open to being wrong? Or has it become something of a religion to them? One thing you can bet on: if we see catastrophic consequences of failure to act, the people who today are working so hard at inactivism will be very, very quiet.

2 comments:

google said...

Steven Levitt and Stephen Dubner answer all the questions about Global warming in their new book "SuperFreakonomics" an extract is in today's UK edition of the Sunday Times. News Review section the title of the article is "Everything you thought you knew about Global warming is wrong"

Everyone on the planet that has anything to do with the Global warming business should read it.

Philip Machanick said...

It's also a good idea to read some contrary reviews before wasting your money. It looks like another attempt at stirring controversy without substance. Plenty of negative reviews at Amazon for example: SuperFreakonomics: Global Cooling, Patriotic Prostitutes, and Why Suicide Bombers Should Buy Life Insurance