Mann on mathematics, alcohol, and 'proof'

‘Proof? We don’t need no steenkin proof’*

*With apologies to Treasure of the Sierra Madre.

Rich Trzupek writes:

In a post over at Peter Guest’s blog, Michael “Hockey Stick” Mann is quoted making one of the most remarkable statements that I’ve ever heard coming out of a supposed scientist’s mouth:

“Proof is for mathematical theorems and alcoholic beverages. It’s not for science.”

He goes on to explain that science is all about “credible theories” and “best explanations” and his gosh-darn critics supposedly don’t offer up any of those.

Now it seems pretty obvious that Mann’s attempt to separate proof from science stems from increasing public awareness that the warming predicted by the high-sensitivity models that Mann and others have championed just hasn’t occurred over the last fifteen years. No matter. You don’t need “proof” when you have “credible theories”.

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These days, when I see ‘Michael Mann says…’ all I can think of are the Martians from Mars Attacks. “Ack ack! ACK ack ack!”


Well, he may be distinguishing “proof” in the mathematical sense versus “evidence” in the empirical science sense. Science cannot be “proven” like a mathematical theorem, only disproven by observations. That at least might be the defense he would take to this. If he also thinks that “evidence” is not useful, then he truly is misguided…


Maybe ‘proof’ isn’t for Science, but ‘disproof’ certainly is.
As in when the predictions of a hypothesis are not substantiated by the observations, the hypothesis is usually deemed disproven..


Mann tweeted the other day,
Russian Ice breaker was breaking up the Ice at the north pole yesterday.
What’s the reason for this,

Science is not about proof
“Some years ago I had a conversation with a layman about flying saucers — because I am scientific I know all about flying saucers! I said “I don’t think there are flying saucers’. So my antagonist said, “Is it impossible that there are flying saucers? Can you prove that it’s impossible?” “No”, I said, “I can’t prove it’s impossible. It’s just very unlikely”. At that he said, “You are very unscientific. If you can’t prove it impossible then how can you say that it’s unlikely?” But that is the way that is scientific. It is scientific only to say what is more likely and what less likely, and not to be proving all the time the possible and impossible. To define what I mean, I might have said to him, “Listen, I mean that from my knowledge of the world that I see around me, I think that it is much more likely that the reports of flying saucers are the results of the known irrational characteristics of terrestrial intelligence than of the unknown rational efforts of extra-terrestrial intelligence.” It is just more likely. That is all.”
math is about proof
logic is about proof
science is about more likely and less likely
one way to understand the difference is to consider this
A) 2+2 = 4
In the case of A we might argue that there is no possible world in which 2+2 does not equal 4. other rather that it is true in all possible worlds. There is no way, no imaginable way it can be wrong. With F=MA, however, we could imagine worlds in which F does not equal MA.
there is no proof in science.

Ken Hall

He is right that science does not do proof. It does theories which are supported by the current data, and those theories remain credible until such time as there is new data to disprove them.
Credible theories require credible data. The problem Mann has, is the CAGW argument has no credible data supporting it anymore. so he has no credible theories either.

Michael Jankowski

Mann disappoints – gavin

Chad Wozniak

More pus from the pustule. Why would we expect anything else from this anti-scientist?
Of course, what he is saying is “Believe me no matter how proven wrong I am.”

‘GlynnMhor says:
August 1, 2013 at 9:44 am
Maybe ‘proof’ isn’t for Science, but ‘disproof’ certainly is.
As in when the predictions of a hypothesis are not substantiated by the observations, the hypothesis is usually deemed disproven..
Actually, not.

j ferguson

I’m enjoying this opportunity to agree with Mann. Science has a lot (maybe everything) to do with disproof but nothing to do with proof. I prefer my proof in a bottle.

Steve Crook

Reluctantly, I agree with Mann. +1 to Mosher.


Steven Mosher says:
August 1, 2013 at 9:45 am
Now suddenly you like Feynman?
Science is about falsification (in Mann’s case the common meaning of the term applies). It is not about “credible theories”. In rare instances, a never-shown-false hypothesis can in fact be “proved”, ie demonstrated objectively “true”, as in the fact that the earth goes around the sun, while rotating & wobbling on its axis, as hypothesized by Copernicus.
The “theory” that the sun & planets go around the earth was credible. The “theory” that phlogiston causes burning & rusting was credible, at least as credible as CACCA is now. Mann, as usual, is dead wrong.
The hypothesis that 90% of (dubiously) observed warming in recent decades (never precisely dated) is due to man-made GHGs & that this effect will have catastrophic consequences has been repeatedly falsified in all its terms.
CACCA has corrupted not only scientific practice itself but the philosophy of science.


He’s right that science only disproves, rather than proves, but he’s basically using weasel words to try to explain why the surface temperature record isn’t playing ball with his favoured theory.
I’d love to know how Mann’s statements plus the divergence between observed and modelled temperatures can equal “settled science” in anyone’s eyes. The null hypothesis is “A doubling of pre-industrial atmospheric CO2 levels will not cause a dangerous rise in surface temperatures”, and it’s a million miles from being disproved.
I see he pulls out the old Big Oil and Tobacco Deniers canards again too.

So proof is for the fools. By extension, disproving anything is also irrelevant. That helps explain the statement and the source.
Now that disproving AGW does not invalidate it, we must accept it – because he said so.


That single quote would make an awesome billboard. Along with an identification of the speaker’s IPCC credentials. The more people drove past it again and again, the more likely they’d finally have the thought “WTF?”


As K. Popper has stated : You cannot prove a theory correct only disprove it. CAGW has been disproved in so many ways that it can no longer be classed as a theory. A warmers wet dream would be closer to the truth.

I actually agree with Mann that science isn’t about proving theories (unlike mathematics). As Einstein said, “No amount of evidence can prove my theory, but only one experiment is needed to disprove it.” In short, science is about disproving theories.
The whole problem with Mann’s approach is that he’s never done any real science, which would mean trying to disprove his hypothesis, rather than trying to support it with endless contortions of the evidence.
Mann is just waving his hands, trying to distract us from the fact that the GHG hypothesis of high climate sensitivity can’t weather (pun intended) the tests of it’s many claims. He’s invoking the straw man of “proof” to distract us from seeing that he’s made no effort to disprove the hypothesis, or to incorporate the work and the data that helps disprove it. No hypothesis is credible unless it weathers those efforts, and “best explanations” have no power, unless they can withstand that sort of assault.
At one time, the GHG hypothesis of high climate sensitivity had at least some credibility to it. But the tests of time, data, and analysis of its predictive power has shown otherwise. No amount of hand-waving about the impossibility of “proof” is going to make that go away.


Nice to see a response by Steven Mosher that isn’t a pithy one liner but a reasoned reply.
With which I fully agree. I’m afraid that attacking a statement simply on the basis that it came from Michael Mann isn’t very scientific.

Jimmy Haigh.

“Are there, or are there not, flying saucers?” is hardly a scientific theory. It’s just asking someone an opinion.

chris y

Dyrewulf says-
“These days, when I see ‘Michael Mann says…’ all I can think of are the Martians from Mars Attacks. “Ack ack! ACK ack ack!”
How about while the Martians are vaporizing people, the Earth-Mars translator one Martian is carrying says- “Don’t run! We are your friends.”


It’s a miracle he didn’t flunk out of kindergarten.

Bruce Cobb

I see he’s still going on about the Jerry Sandusky thing, which is ridiculous. If someone were to say that he is a pimple on the backside of actual science, no one could honestly say he was being compared to either a pimple or a backside. Although, he does act like a horse’s patooty.


This is only one more way Warmists attempt to throw out the TRUTH. Since they cannot PROVE AGW, they attempt to obfuscate to a state of complete confusion, then they can continue with the scare tactics. They cling to the CO2 and models, while claiming the heat is hiding behind the cooling!


Steven Mosher says:
August 1, 2013 at 9:45 am
Of course, your RF example is fine. However, there has to be a contextual element. Science in the FINAL analysis is INDEED about proof. (although it is perhaps better thought of as THE most likely proof in some cases). Relativity wasn’t proven for a good few decades, but proven by observation it was. In the time up to the ‘proof’ it was accepted as the most likely explanation.
The final analysis is what ultimately defines the conclusion of that particular ‘bit’ of science and that is indeed about proof. (I suppose we could elaborate and try and define it as ‘beyond reasonable doubt proof’, too though?)
There is no point in harping on about ‘other’ worlds or other imagined ‘possibilities’ without hypotheses and observations to support them. In the context of AGW/CAGW – the observations are not supporting the hypothesis(es) – and from THAT, the underlying hypotheses (or a significant portion of them, e.g. feedback assumptions/ estimates) are most likely to be wrong.
It appears that Mann is trying to use the ‘inbetween stage’ of not having conclusive findings (or proof if you prefer) as insignificant – which of course, in the context of observational tests of hypotheses – is completely obfuscating the issue!


E = MC^2. Einstein declared it. Others have “proved” it. Is it Science?

RC Saumarez

I agree that science is based on the idea of testable hypotheses and that testing a hypothesis with an experiment that it does not fail does “prove” that hypothesis is correct.
However, much science is based on mathematical axioms that are capable of proof and so “proof” underpins hypotheses and their testing.
Many tests of hypotheses depend on statistics, which if misapplied (as M Mann should know) can be proved to be wrong by mathematical axioms.

“A mathematician is a blind man in a dark room looking for a black cat which isn’t there.”
Yours truly experienced it in looking for the climate’s natural variability cause.


Proving is for mathematical theorems. Disproving predictions is for hypotheses & theories.
On those rare occasions when you can drag an actual testable prediction kicking & screaming out of a CACCA witch doctor, it’s promptly shown false.

chris y

“These days, when I see ‘Michael Mann says…’ all I can think of are the Martians from Mars Attacks. “Ack ack! ACK ack ack!”
Upon reflection, I think a quote from Locutus of Borg applies perfectly to climateers like Mann-
“Why do you resist? We only wish to raise quality of life for all species.”

Owen in GA

who is that “wottsupwiththatblog” that showed up in Mann’s twitter feed. Is someone attempting to spoof this site’s host?

This is a grossly embarrassing “own goal” for “my side” — i.e., your side.
I think climate science is mostly pseudoscience, and I’ve been sceptical about global warming for many years. But the empirical evidence for a scientific theory consists of its passing tests. It’s called the hypothetico-deductive method, because an observational consequence is deduced from a hypothesis, and if actual observation is found to confirm what was predicted would be observed, the hypothesis is “corroborated”.
It’s not at all a matter of “proof” — or at least nothing like proof in mathematics. The main reason why climate modelling should command little confidence is because the predictions of the models fail the “tests”, inasmuch as they are even subjected to them.
If I were you, I’d take a closer look at whoever is giving you completely misleading accounts of mainstream philosophy of science.


The “best explanation” at the time for the rumbling of the volcano was that the Volcano God needed the attentions of a comely young female. The “best explanation” at the time for sickness was that there were ill humours in the blood, and they needed to be drained. The “best explanation” for gravity was that the Earth was flat. And, so on.
This isn’t science. It is old timey, primitive superstition.

Pat Frank

Mann is right in the sense of distinguishing mathematical proofs from scientific demonstration. Theories in science are never proven; they are always provisional and subject to revision in light of new facts. Theorems in math can be definitively proven, never to be unproved.
The difference stems from that science is non-axiomatic and data-driven. This fully and finally distinguishes science from mathematics and philosophy. Nothing in science is ever taken to be self-evidently true.
On the other hand, Mann’s comment that, “Science works in evidence through best explanations, most credible theories…” is sloppy and allows his work wiggle-room. Science works on falsifiable theories. “Credible” as Mann used it merely means ‘believable.’ ‘Believable’ is a wholly inadequate criterion for scientific theory. Climate modelers believed the hockey stick because it suited their prejudices. Their credit did not make the hockey stick scientific.
If Mann had used the proper criterion, ‘falsifiable,’ it would lead immediately to a question very uncomfortable for him: Is the hockey stick falsifiable? The answer is a definite no. And a critical examination shows that the hockey stick is not even science. It’s based on no physical theory at all. So, Mann must equivocate if he’s to preserve his image.
The statement that I found most egregious was his stunningly self-serving, “One side, us, the scientists, have to be true to our principles, have to be truthful to our audience, have to state our findings with appropriate caveats,…” when we all know he’s done the opposite. He has betrayed science at every turn, obscuring his methods, withholding data, misrepresenting his results (‘I never calculated that r-squared, Senator. It would be a wrong and foolish thing to do.)
If the Steyn case ever comes to trial, I hope to see Steve McIntyre in the witness box: ‘Mr. McIntyre, could you please describe the contents of the ‘Back to 1400 CENSORED” directory.’
Mann also repeats the lie that nearly originated with him, “Scientists and those looking to communicate the reality of science are up against this juggernaut, this extremely well-funded, well-organised smear campaign by … the fossil fuel industry.” What a bald-faced lie. And it’s a lie so absent of substance that a reportorial naif could prove it false.
But it’s repeated over and over, widely and uncritically accepted, and no reporter ever gets to the bottom of it. Maybe that’s because it suits their prejudices. Like the climate modelers’ embrace of the hockey stick because it seemed to “prove” the water vapor feedback they’d built into their climate models, too many reporters accept the lie about fossil-fuel funded smear campaigns because it seems to “prove” the evil capitalist greed they’ve built into their political models.


What other nonsense can one expect from an alleged scientist, Mann, who rewrote the entire climate history of the Holocene Epoch. Nothing that he says or writes has any credibility in my eyes.
His rewriting of climate history is equivalent to the work done by the Holocaust Deniers. So who is the true denier?

Steve Oregon

Dyrewulf says: August 1, 2013 at 9:39 am
These days, when I see ‘Michael Mann says…’ all I can think of are the Martians from Mars Attacks. “Ack ack! ACK ack ack!”
And “We come in peace” just before they begin slaughtering everyone in sight.

Tim Clark

n nnnnnnnnnntkgrrrrrrrrrr lggggggggggggggg6ky
Opps, sorry.
Those are the keys recorded when my face hits the keyboard after falling asleep.
Happens every time I read a Mannian brain fart.


Makes sense , Mann has never worried about ‘proof ‘ for his work , as self promotion and dogma are all that matters to Mann and hang the ‘facts ‘
You like to think that such views would cause other in science given their views on such ideas , but sadly they prefer playing the three wise monkeys or getting their noses the AGW funding bucket .to calling out such BS .


Semantics, maybe.
Science does not work on proof so Mann is correct but to prove a hypothesis data etc. is required by those trying to prove/disprove the idea. Methinks that was what Mann meant – proof is not required for his science.


Steven Mosher says:
August 1, 2013 at 9:45 am
A) 2+2 = 4
In the case of A we might argue that there is no possible world in which 2+2 does not equal 4. other rather that it is true in all possible worlds. There is no way, no imaginable way it can be wrong. With F=MA, however, we could imagine worlds in which F does not equal MA.
The limit of your imagination and its selective use does not prove A and B are different. What you said proves nothing.


I think the operative is “credible”. Since he and his data aren’t…then game over.

Nancy C

Stephen Mosher said:
“With F=MA, however, we could imagine worlds in which F does not equal MA.”
Ha ha, no, this is wrong. The defined unit of force is kgm/s^2. Can you imagine a world where MA does not equal MA? Of course, in another universe you could define what force means differently, but then again, you could define it differently in our universe, too, if you wanted to do something useless.
I agree, though, that science isn’t about proof, it’s about laws. Once you show a proposition to ever give wrong results, it is known to not be a law, so it’s now known to not be valid science.


Kev-in-Uk says:
Relativity wasn’t proven for a good few decades, but proven by observation it was. In the time up to the ‘proof’ it was accepted as the most likely explanation.
Well not quite. So far the theory has not been falsified therefore as Feyman has stated it likely that it is true. But there is no reason why, like Newtons theory that is a mere approximation once someone has dug into and explored the quantum aspects of a more complete formulation.


He was just pointing out that people who don’t understand science dand proof while scientists demand evidence. Way to be in the wrong, lol.
REPLY: Ok then next time you complain about some issue here on WUWT, I’ll direct commenters to address your concerns by just providing “best opinions” rather than any proof. Way to shoot yourself in the foot. – Anthony


@Steve Mosher. IIRC, the philosopher Bertrand Russell spent 42 pages of a book ‘proving’ that 2+2=4.
Then again, we have surely not forgotten that the old English verb ‘to prove’ really means ‘to test’ – but who is Mann going to allow among us mere mortals to test his ‘theory’?

Tom Norkunas

Ahh. Mann-made global warming.


Steve Crook says:
August 1, 2013 at 9:52 am
Reluctantly, I agree with Mann. +1 to Mosher.
Mr. Mosher doesn’t like the part of RF’s lecture that comes before the flying saucer bit:


Well there may not be real scientific ‘proof’ in the absolute sense, but there is in the legal sense, where proving beyond a reasonable doubt requires opposing hypotheses be presented and a jury of 12 independent minds view and full comprehend the supporting and opposing hypotheses and unanimously agree on one. In the court of scientific opinion, where fully independent minds analyzed all the evidence, Mann’s high climate sensitivity hypotheses would fail miserably.


Best explanation is a fair description for soft (narrative) sciences lacking provable mathematical theorums. Mann’s problem is he is in denial when it comes to recognizing climate science as a soft science.

Mike M

I think it’s hilarious how Mann can wrap himself in the truth of science being about credible ideas while making a mockery of his own credibility fighting off FOIA requests.


Feynman also said “It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong.”
That is why efforts at fasification are such a important tool for science.