Monday, January 26, 2015

Freeman Dyson's Strange Skepticism on Climate Change


Sometimes being an out-of-the-box thinker has its downsides.

Famous physicist Freeman Dyson was recently interviewed about his climate change skepticism via email by Steve Connor, a respected science journalist for The Independent. I thought the exchange was fascinating, and highlights interesting flaws in how even an unquestionably great scientist can fail to understand the Philosophical underpinnings of how science assesses evidence for supporting (or falsifying) conclusions.

For example, I thought this was a very good question on the part of Connor:
"Isn't it a bit risky for me and the rest of the general public to dismiss this vast canon of climate science as just "fuss" about global warming when all I've got to go on is a minority opinion? "
The journalist (and I) think the answer is clearly yes -- it is risky; but, Dyson apparently thinks the answer is "no".

It was also interesting to look at Dyson's actual arguments on why experts get it wrong.  Here is one selection from Dyson:
"My impression is that the experts are deluded because they have been studying the details of climate models for 30 years and they come to believe the models are real. After 30 years they lose the ability to think outside the models. And it is normal for experts in a narrow area to think alike and develop a settled dogma. The dogma is sometimes right and sometimes wrong. In astronomy this happens all the time, and it is great fun to see new observations that prove the old dogmas wrong."
One of the unstated premises in his argument is: "The more one looks at data and models the more likely one is to become 'deluded' about the subject at hand."   So much for being able to learn by studying things carefully and at length for 30 years!   This unstated premise is false, and is easily shown to be so on empirical grounds. Contra Dyson, perhaps an alternative reason that experts come to think the models are real after much study is because of the proper way to assess the evidence at hand. Compare the following: It's hard to think outside the model that stars are self-luminous gaseous spheroidal celestial bodies of great mass which produces energy by means of nuclear fusion reactions; because, well, all the evidence at hand shows us that this is really what they are!

Elsewhere in the article, Dyson demurs he's not an expert, and will not talk about details; but, the methods of study are publicly accessible for all to review, and the details (i.e. the data) are also readily available. Compare this to a detective that decides who the murderer is, but who will not talk about the details of the crime scene when questioned by other detectives. The details are what matters!

Dyson's comments on "settled dogma" are also quite strange.  Is it just luck that sometimes the dogma is right and sometimes wrong?  Of course not.  Compare the following claim about desert climates: "Sometimes it rains and sometimes it's sunny."  Indeed, but how often it rains as compared to how often it's sunny really matters.  Likewise, how often a large consensus of scientists from multiple fields are right on a shared subject, and how often a large consensus of scientists from multiple fields are wrong on a shared subject really matters (as John Oliver points out in a very funny skit.) That is conveniently not noted by Mr. Dyson, other than to say the arguments have become heavily politicized, and thus not fairly reported in the media.  (This later reasoning of Mr Dyson is an ad hominem fallacy, by the way.)

There were other failures of evidence-based thinking on Dyson's part too, but I though I'd go after the easy ones to see. Overall, being an out-of-the-box thinker can help in generating creative insights, but it can also hamper one's ability to assess confirmatory and/or invalidating evidence, especially when someone relies on personal intuition at the expense of evidentiary thinking.