By the standards of very clever men who believe some very silly things, Harry Kroto is a quite unremarkable scientist. Unlike some other Nobel prize winners, he is not an enthusiastic Nazi, a Stalinist, a eugenicist, or even a believer in ESP. He did play a prominent, and I think disgraceful part in the agitation to have Michael Reiss sacked from a job at the Royal Society for being a priest. But the video of his speech at the Nobel laureates meeting this year in Lindau, Bavaria, is something else. Much of it is great stuff about working for love, not money; and about the importance of art, but around eight minutes in he goes off the rails. First there is a slide saying (his emphases): "Science is the only philosophical construct we have to determine TRUTH with any degree of reliability." Think about this for a moment. Is it a scientific statement? No. Can it therefore be relied on as true? No.
But formal paradoxes have one advantage well known to logicians, which is that you can use them to prove anything, as Kroto proceeds to demonstrate. Or, as he puts it: "Without evidence, anything goes." Remember, he has just defined truth (or TRUTH) as something that can only be established scientifically. So nothing he says about ethics or intellectual integrity after that need be taken in the least bit seriously. It may be true, but there is no scientific way of knowing this and he doesn't believe there is any other way of knowing anything reliably.
Note how this position completely undermines what he then goes on to say – that "the Ethical Purpose of Education must involve teaching our young people how they can decide what they are being told is true" (his caps). Again, this is not a scientific statement, and therefore cannot, on Kroto's terms, be a true one.
The rest of us, of course, are perfectly free to believe that education should involve the promotion of critical thought, or at least to consider the question seriously. We are under no obligation to believe anything half so silly as that science is the only road to truth. We can reasonably argue that there are lots of ways to establish truth that are not scientific. Obviously they rely to some extent on the sifting and weighing of evidence, but that doesn't make them part of science, or else every member of a jury would be a scientist.
In a similar way, we can believe that ethical truths exist, even though these clearly aren't scientific, or the products of science; but Kroto can't. Not that this stops him. Like anyone else who is sane he talks as if ethical truths do matter, and exist.
When he goes on to say: "The teaching of a sceptical, evidence-based assessment of all claims without exception is fundamentally an issue of intellectual integrity," he absolutely believes that what he's saying is true (and so do I for that matter). But he has no scientific grounds whatever for believing it could be true and it is impossible to imagine any.
What makes this even funnier is that he then starts talking about the Galileo affair. He asks his audience how many of them could recapitulate Galileo's arguments for the Earth's going round the sun. Hardly any can. "See!" he said. "You've accepted it. You've accepted it without evidence. And 70-80% of people do that."
I'm prepared to accept on trust his figure of 70-80% even though it is of course very low. If by "evidence" he means "people familiar with Galileo's arguments" it's unlikely to be more than about 1% of the scientifically literate; and if he means "people who have actually read the source material", the proportion is just about infinitesmal. The idea that we should test everything against the evidence crumbles to dust the moment it is itself tested that way.
Still, let's assume that Kroto has himself studied Galileo's arguments for heliocentrism. He should therefore be familiar with the contemporary scientific arguments against them. Because if there is one thing that has been established in the history of science in the last 50 years, it is that in strictly scientific terms, and going by the evidence available to him and to his contemporaries, Galileo was wrong and Cardinal Bellarmine was right. Heliocentrism was a beautiful theory, and Galileo would have been free to teach it as such – but the observation of stellar parallax, or rather the discovery that none could be observed, should have knocked it on the head (for a fuller explanation, see here and here).
Obviously it was wrong to suppress Galileo's views entirely; but if only what is scientifically justified may be taught, then Bellarmine would have been right to do so.
This isn't just a matter of historical curiosity. The illogical positivism of Kroto's talk is symptomatic of a widespread problem. Although Kroto is exceptional in his self-confidence and lack of intellectual self-awareness – few other people would state as baldly as he does that science is the only way to establish the truth – no one in the audience seems to have reacted with a healthy giggle. They may have felt there was something a bit off about the idea, but the full absurdity was veiled by layers of deference and convention. The great attraction of telling everyone else to think, to question, and to take nothing for granted is that it makes a very pleasant substitute for doing these things yourself.
• This article was amended on 6 July 2011. It originally placed Lindau in Austria. This has now been corrected