Monday, 5 May 2014

Of free thinkers, blind sheep, and bloodletting

A month ago I began a series of posts that were ostensibly about climate change, but were really an attempt to chip away at what I think is a misunderstanding about science in general, even amongst many scientists. As I've said before, climate change is not my specialist area, and when it comes to explaining, justifying and arguing climate science, there are many other people far more qualified and far more patient than myself. Climate science just happens to be a good example of the point I want to make.

I've taken some time, because I wanted to get a few things out of the way first. For a start, I am not interested in the climate-change sceptics who are ignorant, ill-informed or dimwitted. They are a problem, but they are not an interesting problem. We all fall into that category sometimes: we make silly arguments because it suits our prejudices, or our mood, or we just don't want to accept that we're wrong. But the people I am interested in are those who occasionally take the time to think very carefully about a topic, to mull over many different perspectives, and different arguments, and take into account all of the information they have to hand, and then publish their honestly and scrupulously considered opinion. What is interesting to me is when those people express serious scepticism of the theory of anthropogenic climate change. As one example I put forward the critic Clive James, who I argued is very sharp indeed, but nonetheless mocks the conventional climate-change wisdom.

Now, he has every right to be publicly sceptical, and I sympathise with his complaint that the environmental community has its fair share of sawn-off wackos who would continue to believe in climate change even if the evidence proved otherwise. But I nonetheless feel that he is missing an important point. Part of that point is that to be usefully sceptical of the science requires an expert trained practitioner in that science, and the best a non-specialist can do is simply check that the scientists themselves are being suitably suspicious of each others' work. But that is not the whole story.

He also complains that in his experience expert predictions rarely amount to anything, and although it is important to make a distinction between regular expert predictions (which are notoriously unreliable) and scientific predictions (which, in their purest form, have been rigorously tested) [1] this is indeed a problem with climate change, even if some climate crusaders are reluctant to show weakness and admit it. The fact is that the standard climate-change hypothesis is not as rigorously tested and verified as, for example, the theory of gravitation -- and oh how I cringe when anyone claims that it is! So there is legitimate room for doubt, and some of that doubt is expressed by experts in the field.

In James's 2009 piece, he cited as a dissenter Richard Lindzen, formerly a professor of atmospheric science at MIT. Now, the seasoned climate campaigner will reply that Lindzen's theories have been roundly thwarted, and that he is just bitter at being proved wrong, and anyway, he has now joined the Koch-funded Cato Institute, and so his credibility is completely shot. I would argue that all of that is irrelevant. Presumably a determined sceptic can unearth other impressively titled experts who can also present convincing arguments. And, even though they are experts in the topic and I am not, I would argue that they are also irrelevant.

How do I dare to do that? Aren't they the expert, and not I? Yes -- and precisely for that reason, I have no choice but to defer to the opinion of the overwhelming majority of other experts. 97% of climate scientists support the standard climate-change hypothesis, which means that for every big-shot scientist who opposes this theory with a water-tight argument, there are 32 other big-shot scientists who can rip gaping holes in that argument. Can I confidently parse those arguments? No. But I have to accept the sheer weight of numbers.

I admit that this is difficult to do. There is a natural human tendency, no matter how smart we are, to support the underdog. If only 3% of scientists dissent, then that must be because they are the good honest free-thinking sceptics, and the rest are just sheep. Our sweetly romantic minds may love that view, but it's demonstrably nonsense. Imagine that scientific opinion reversed (perhaps due to a discovery of the notorious Hannam Effect), so that only 2% of scientists did accept climate change -- would it now be much more convincing?

This is even more difficult to accept if you are unusually clever. You might be one of those people whose reaction is to cry, "This is intolerable! Not only am I the smartest person I know, and not only am I sure that I am smarter than all those egg-headed physicists and bearded biologists, but I am also extremely level-headed and practical and brimming with common sense, and plus I have absorbed a lifetime of experience." You might protest, "I have spent my whole life seeing through other people's lies and uncovering the truth, and this is no exception." Yes, you might be an insufferable dick. But if you really are so smart, then you will be able to accept that our understanding of the world is fraught with uncertainty, and although there is some risk involved in following the advice of the scientific experts, that is the best advice we're going to get.

What makes it yet more difficult is that we are continually told that, so long as we are sharp of mind and good of heart, the truth will be clear, no matter how seemingly tricky the topic. In a movie set in the Middle Ages, everyone thinks like a medieval moron, except for the hero, who deplores slavery, espouses greater rights for women, and sports the same hairdo as everyone else at this year's Oscars. If the opportunity ever arose, he'd probably also reveal that he believes in plate tectonics, wave-particle duality, and the principle of natural selection, and also has a pet theory that prior to humans the Earth was inhabited by giant reptiles.

Those clairvoyant fictional heroes delude us into believing that we could do the same. I would love to believe that if I lived in the age when diseases were routinely "cured" by bloodletting, I would have had the presence of mind to realise that it was a barbaric and harmful practice, and never allowed it to be used to cure my toothache. But in reality I would have had as little understanding of the human body as anyone else, and my strenuous intellectual objection ("It'll hurt!") would have been no more justified then than it was when I got a blood test last month. None of us would have had the least clue what was going on, not me, not you, and not Richard Dawkins, Paul Krugman, Steve Jobs, Nate Silver or Malcolm Gladwell.

All of these issues arise in many areas of science, and especially in medicine. Climate change is one of the few topics where the majority expert opinion is easy to identify, and where the majority is overwhelming; if it was a 60:40 split between those for and against, then the situation would be far less clear. But it is clear, and the real question is what to do about it. Now that is a problem for our finest minds to devote themselves to.

Coda: Nightmare scenario.

1. There is a nice discussion of the poor track record of expert predictions in Tim Harford's book Adapt. The special role of scientific expertise is succinctly detailed in Harry Collins's Are we all scientific experts now? Harry and I will be discussing that very book at this year's Hay Festival on May 23rd.


  1. I'm just a dumb person, but that's a perfect explanation for how I have always felt (and hoped!) about science-y stuff when I'm talking to climate change deniers, or any conspiracy theorists,'s hard to argue with those freaks when they know more about the subject than you do, even though you know you're right without knowing how you know! Thanks, Mark. Brilliant stuff.

    1. Is that by any chance meant ironically, Oli? Mark's article is rational but puts too much weight on the alleged '97% consensus'. The important question is not whether CO2 causes global warming, but whether we are certain that increases in it will inevitably cause catastrophic change. We need to be fairly certain of this before we can justify taking expensive and dubiously effective measures that will damage the poorest in our society. Adaptation is the answer, not mitigation - we can adapt to what does happen, when it happens, rather than attempting to mitigate consequences that may prove overstated if not imaginary.

    2. No irony whatsoever, and I believe we have to do something now. Your approach is exactly what needs to be crushed by people who actually realise that immediate action is imperative.

  2. I very much like the word "denier". I think it's an unscientific ad-hominem accusation that's right up there with "heretic". It's no substitute for sincere discussion. Not when Prince Charles goes to Cancun in his private jet. Not when we export manufacturing to China and China doesn't care. Not when Germany will be burning brown coal, and not when thorium power has been sidelined for decades.

    And the point of discussion isn't whether CO2 emissions will cause harm, it's how much harm, compared to other threats. Overpopulation is the elephant in the room. A pandemic will fix our global warming problems at a stroke. But to hell with that, let's redirect all astronomy funding to climate science. Then when the asteroid hits, we'll have plenty of climate scientists to fix the decades-long 'nuclear winter'. And we can tell ourselves that we never saw THAT coming.

  3. If you read carefully through my article, you will notice that my points are not meant for you; they are for people who think coherently.

    You should also notice that the "point of discussion" in this particular article is whether a reasonable person should accept the theory of anthropogenic climate change, not what we should do about it, and not the relative importance of other problems (whether real or inflated in the reader's fevered imagination).

    As for "denier", whenever I have used the word (which has been rarely), I have meant it only in the literal sense, as in someone who denies the existence or truth of something, which is hardly pejorative. There are only so many synonyms for doubt, dissent and disagreement. My intention should have been clear from the general tone, but, now that I think about it, many much simpler things should have been clear to you as well.

    I have no problem with the word being applied to me when appropriate. In fact, in future I will try harder to be a "Gibberish Denier" when moderating comments.

    1. Mark, lets talk about relativity and gravity and black holes. Pretty please with a cherry on top?

  4. What's downright comical here is that you deride those who "don't believe" in climate change while you "believe" in climate change. What, precisely, is the difference here? You didn't do the science; I'm confident you don't truly understand the science. Yours is nothing more than a derivative belief system; a religion masquerading free thought. Bow down to your god, sheep.

  5. Did you even read the article, Anonymous? Good grief.

  6. Oli, many people read; few understand...!

  7. Have you looked into Lubos Motl's views on climate change? I can't stand to read very much of him, since he's one of these smart people who seems blind in various painful ways. His expertise on string theory really doesn't to me give him much credibility on climate change, but I know its one of his favorite topics.
    Reading him you get the feeling that the intelligence required for doing theoretical physics is so much greater than that required for any other type of work to understand some aspect of the world. Maybe he's another example of the kind of person you mention in this post.

    1. I just took a look. I'd say thanks for pointing him out... but I'm not sure that's quite what I mean! Maybe a very smart brain is like a very fast car -- hard to keep on the road.

  8. LMAO!! You hear that fellow scientists? Only use your brain in ways that Matt Hannam deems to be correct. What a load of malarky.

  9. Interesting metaphor. Its been a long time fascination of mine how some people can be so perceptive in some ways, and so far off in others.
    Yeah, I guess you are focussing on some of the more reasonable climate change skeptics.

  10. Excuse mi English not primary language. I talk of the discourse in science and believe that the climate change is real not an imagined item.There will be consqueunces for actions taken or not taken. Mi own studies reveal a higher ice melt this upcoming Summer by a fraction of 9%. It is large, no?

  11. I just watched your hero Bill Nye get annihilated in an interview. His facts were all wrong and he had to resort to yelling and name calling. Typical scientist geek who got beat up as a kid and hasn't gotten over it. We own you science guys on climate. You've been crying wolf about it for 40 years and there has been no significant legislation in support of your threats. Tick tock tick tock. You should put a carbon emissions counter on your website that counts how you're ruining the Earth with the server power required to run this thing. You don't care about the Earth.

  12. Mark, when you say "97% of climate scientists support the standard climate-change hypothesis", what exactly do you mean by "the standard climate-change hypothesis", and where did you pick that figure of 97%from?

    I'm a scientist who has been researching climate change for a number of years now, purely from my own passion for science, i.e., unfunded research. I've read several thousand papers on the subject, downloaded and analysed quite a lot of climate/weather data sets & carried out my own research - does that include me in your target audience for this post?

    Anyway, my reading of the scientific literature indicates that there is actually quite a wide range of views on the causes of climate change, and how recent climate change compares to past climate changes.

    In particular there seems to be a range of views among climate researchers over how much of the climate change of the last century is "anthropogenic" and how much is "natural". I've written a summary of some of these views, giving examples, here:

    What do you think? Do all of those views correspond to "the standard climate-change hypothesis"?

    If they do, then Clive James' views seem to be in keeping with somewhere about 4 or 5 on the scale, so his views aren't as anti-science as you seem to be implying.
    However, if "the standard" hypothesis refers to parts of the scale that Clive James disagrees with, then where did you get your figure of 97% from?

    The claim from the latest UN IPCC reports that it is “extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century” is sometimes assumed to represent a "scientific consensus". Is that the "standard climate-change hypothesis" you are referring to?

    Because, if so, the IPCC process isn't actually capable of capturing the actual scientific consensus on any topic, let alone a contentious one like climate change. I also wrote a discussion of the problems with the IPCC process here:

    Have you looked at the IPCC process yourself?


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