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Category: Book review

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February 23, 2009 | 25 Comments

What appeal to authority means and what it doesn’t

This article is meant to be the first is a small series of demonstrations of how not and how to argue for or against climate activism. The level of argumentation on the web has long passed subbasement (people have been calling each other “Hitler” for over two years), but worse are the misuses and misunderstandings of logic. People throw around terms like ad hominem and appeal to authority constantly, without understanding what they are saying.

My hope is that when you see an abuse of the type outlined, you simply cut and paste the link to these pages. This will save us all a lot of time and unnecessary typing. I hope.


A prominent climate inactivist forwarded me a document in which he argued against some of the more catastrophic claims said to be due to global warming.

At the beginning of his piece he implied that James Hansen, who is the best known climate activist, should not be trusted because Hansen only had training as an astrophysicist and not as a climatologist.

This is a poor argument because the author of the piece was not himself a climatologist. If you must be an official climatologist before being allowed to comment on climatology—a position that is logically valid given that you can satisfactorily define “climatologist”—then just about everybody, activist and inactivist, must shut up. Including the author of that piece—and almost certainly, including you.


Mr Activist: this means that you would not be allowed to say anything whatsoever about global warming except to repeat what you have been told by an official climatologist. You would be allowed to say “Mr Climatologist says B” and nothing else.

(“B” can be any statement or proposition about climatology only—it cannot be about politics or health or biology or anything else.)

Mr Activist would not be allowed to say “Mr Climatologist says B, and you’re a fool not to believe it.” Pause and understand this. The reason is that he is not qualified to say what and what is not foolish because he is not a climatologist.

If an official climatologist says “B, and people would be fools not to believe it,” then you can repeat that statement. But you cannot adorn it, nor comment further, nor say anything else. You can repeat what you are told by your betters and then you must keep quiet.

The only exception to this logical rule is that if everybody, activist and inactivist, agreed on the additional premise, “People that do not believe what official climatologists say are fools.” Then you can logically say, “Mr Climatologist says B, and you’re a fool not to believe it.”

But almost certainly, everybody would not agree on that premise. Let’s see why.


The prominent inactivist made a logical mistake by arguing “Because Hansen is not a climatologist, his statements on climatology are false.” This is only valid if only climatologists make true statements about climatology and if non-climatologists always make false statements about climatology. Is that true?

Obviously not. Plenty of climatologists have made statements about climatology that turned out false in fact and in theory. And plenty of non-climatologists have made statements about climatology that turned out true in fact and in theory.

Because of this, it necessarily means that anybody is allowed to say anything they want about statements of fact or theory about climatology. This includes both activists and inactivists. We can now see that neither side can accuse the other of making a logical mistake by talking about climatology.

So stop arguing about this point!


Suppose Hansen is an official climatologist and he makes the statement, H = “The global average temperature in 2010 will be at least half a degree hotter than in 2009.” (Whenever we see ‘H’, we must remember that it stands for “The global average…”)

If an activist then says, “Hansen, an expert, says H. Therefore, because Hansen is an expert, H is true.” This argument is invalid; the activist has made a mistake. H cannot be true because Hansen said so. The logical error made is called “appealing to authority.”

Most know of this mistake and avoid obvious instances of it. But see 5.

Suppose a second activist said, “Hansen, an expert, says H. Therefore, because Hansen is an expert, H is likely to be true.” This is not a mistake and is a rational thing to say. This is because experts making statements like H are often, but not always, right. Therefore it is rational to suppose that the expert is likely to be right again.

The statement made by the second activist is an appeal to authority, too, but a sound, inductive one.

Mr Inactivist: it does you no credit to accuse non-climatologists of being irrational if they are making arguments of the second type. It is often wise to appeal to authority like this, and is what we all do when we enter an aircraft, trusting the pilot to get us safely to our destination.


Most will agree that Hansen meets the definition of climatologist, but then so does your author, and so do several people (like Dr Lindzen) who do not always agree with what Hansen says.

Now we have trouble. For if only official climatologists can make true statements about climatology, and if two (or more) official climatologists make contradictory statements about climatology, then we have a logical contradiction if the premise “Only climatologists make true statements about climatology” is true. We have already seen it is false, so we are safe.

But suppose Mr Activist says, “Most climatologists say B. Therefore B is true.” This is the same logical error: appeal to authority in the deductive sense.

Let the second activist say “Most climatologists say B. Therefore B is likely to be true.” This is a perfectly rational thing to say.

Even more, the first premise appears to be true in fact: Most climatologists do agree on most statements B about climatology. Therefore, it is rational for people, and their close cousins politicians, to say to themselves “B is likely to be true.”

Mr Inactivist: your only appeal, if you believe B to be false, is to marshal arguments against B. You must not call B a “hoax” or use other disparaging terms as you risk being guilty of appealing strictly to your own authorities (however, there is more to say here, but we’ll save this for another time).

Mr Activist: Because you have reasoned B is more likely to be true, you cannot say “Therefore, everybody must believe B.” To do so is to make the same appeal-to-authority logical error. You must also not express amazement that anybody dare disagree with B for the same reason, and because you must remember that the inactivist has consulted his own authority or set of facts and is arguing inductively just as you are.


Mr Activist, you must not say that Mr Inactivist’s authorities are ineligible because they do not agree with your authorities. This is the same logical error: appeal to authority once more.

And it is a foolish thing to say because you risk defining “expert” solely as “somebody who agrees with what I want.” That is not a logical error, but it is asinine.


Finally, Mr Activist, you must understand Mr Inactivist is making an inductive, and therefore rational, appeal to authority, when he argues “Yes, most climatologists say B, but I believe they are mistaken because these other climatologists claim to have shown where the first are in error.”

Thus, if Mr Inactivist says, “Therefore, B is likely to be false”, then he has said a rational thing. But if he has said, “Therefore, B is certainly false”, then he has made the same error and you can call him on it.


Update: I want to leave as an exercise about how arguments about “peer review” and “consensus” fit into the appeal to authority arguments. After you have said something about “peer review”, then read this article.

December 2, 2008 | 6 Comments

Breaking the Law of Averages on Amazon

Breaking the Law of Averages

The book is now fully available at Amazon, and should be available in other outlets already or soon.

It goes without saying that the book is the perfect Christmas, Hanukkah, Eid-Al-Adha, New Year’s, Oshogatsu, Holi, Bodhi Day, Birthday, or Anniversary gift. But I’ll say it anyway: your loved-ones will despise you if you don’t buy them a copy.

Now, many people are busy this time of year, but will certainly want to include a review of the book on Amazon’s review page. With that in mind, and me being the helpful and generous soul that I am, I have included a couple of reviews that you can cut and paste right into the form, thus saving you scads of time.

A book so unbelievably beautiful that I wept when I first beheld it.

The word genius is certainly overused, so I see no harm in using it once again for this marvelous book

It would be a complete and utter moral failure not to own a copy of this lasting work.

If there is anybody left who wants a signed copy, there are two ways to get one: (1) Send an email with SIGNED COPY as a subject heading to (cost is US$32); (2) Buy a copy on, say, Amazon, and bring it to Manhattan for me to sign. I am easy to find; I wear a brown fedora (in the fall/winter), am tall, and have a distinct statistical presence. You can’t miss me.

December 1, 2008 | 20 Comments

The Malcom Gladwell 10,000 hour genius certificate

The best explanation for Malcom Gladwell’s (Blink, Tipping Point) success is provided by the Annals of Improbable Research in its Luxuriant Flowing Hair Club for Scientists.

The editors of that esteemed journal posit that “The public loves to see and applaud scientists who have luxuriant flowing hair.” The club originated after researchers wondered after Stephen Pinker’s meteoric rise in scientific circles, whose hair had “long been the object of admiration, and envy, and intense study.”

Everybody can immediately bring to mind that greatest of all 20th century scientists, Einstein, whose hair was wildly out of control, a condition which we thus associate with genius. Compare, for example, the locks of Pinker and Gladwell.

Stephen Pinker Malcom Gladwell

The soundness of the theory is obvious.

Gladwell, who has ridiculously poofy hair, is out with another book, this one statistical in name: Outliers: The Story of Success. I often say there are no such things as outliers; and I say it again here. Outliers are data points that are too extreme to fit your preconceptions. Here, outliers are people who do exceptionally well at certain tasks.

Anyway, one of the main—shocking!—findings of Gladwell’s book is that—wait for it—genius takes hard work! Some people might be gifted but they still need a healthy dose of honest toil before they find their fame. After thinking about this deep truth, I have come up with a new joke, which I preview for you today. Tourist: “How do you get to Carnegie Hall?” Me: “Practice!” Ha ha ha! Feel free to pass it along.

No, I dishonor Gladwell. His real contribution comes in putting a number to the time required to reach genius level, a task which nobody thought to attempt before. It’s 10,000 hours. It works like this. Pick an area in which you would like to excel, like ballet. Then practice for 10,000 hours, after which you will be a genius.

Business people love Gladwell because of his obvious talent for finding deep but elusive truths (like the value of hard work) and phrasing the truths in ways simple to understand. Thus, my prediction is that it won’t be long before companies begin issuing genius certificates for those employees who have amassed the requisite time in areas such as “horizontal segmentation analysis.” Since earning 10,000 hours only requires about five years of normal work, we’ll soon be flooded with “geniuses”, or with people who claim that they are.

This won’t be the first time we see such eccentric behavior from business people. We currently have a healthy surplus of “Six Sigma Black Belts” (a term supposing proficiency with a type of statistical analysis), and hip Apple (Computers) has a ready supply of folks to be “Genius Bar” hosts and hostesses (a nicely hollow—but hip—phrase).

If you want to know more about the book, you can visit Gladwell’s own page, where he asks himself a bunch of questions and then answers them as if he is suspicious of his questioner. His announces that the main goal of this book is “to make us think about the world a little differently.”


(To anticipate a criticism: yes, I am jealous. I wish I got one-tenth of what Gladwell gets for a speech. And, yes, Gladwell also goes on and on about what can be termed “luck”, the component necessary to accompany practice and talent to ensure success.)

November 29, 2008 | 8 Comments

Breaking the Law of Averages has finally arrived (almost)!

The book is finally — almost — in the distribution system!

Breaking the Law of Averages

You can sign up to pre-order at Amazon in the States.

Amazon in Germany. (Note: The book is still in English!)

Or Amazon in the U.K.

Doesn’t seem to have reached Barnes & Noble or anywhere else, yet. I’ll update everybody here once it’s available generally.

If you are anxious (a natural feeling) you can buy it immediately at the publisher: click here.

Or if you are feeling the need badly, there’s always this book.