## Sunday, January 02, 2005 ... //

### "Consensus science"

Let's look at one more speech by Crichton, one entitled

• "Aliens Cause Global Warming".
He gave it at Caltech in 2003.

Crichton praised the ideals of science and the integrity expected from the scientists. He criticized

• the dangerous mixture of science and politics
• using the "consensus" as an argument, although consensus belongs to politics, but not to science
• tricks pretending that the existence of a mathematical formula justifies knowledge about a subject that is clearly seen to be uncertain
• holding on to popular notions, long after definitive, reproducible observations had proved these notions wrong
• refusing to examine new research which overturns existing theories and humiliating scientists that are politically inconvenient

Crichton may be a highly successful novelist, but otherwise he can't hide that he's a hard scientist that just happens to earn money as an artist. His degress are from anthropology and medicine, but he could clearly earn other degrees, too. He had to do a lot of research in science and technology before he wrote any one of his technothrillers. His essays are very rational. They are based on purely scientific approach to the questions. He's able to deal with a lot of sources and references.

This speech is no exception. He first explained that the only meaning of some equations in science is to express our prejudices using the language of mathematics. His first example is the Drake equation that was proposed to calculate the chances of finding extraterrestrial civilisations but whose all variables are completely unknown; in Crichton's opinion, the Drake equation was the first modern example how scientifically sounding arguments were used to argue that we know something that is clearly unknown. This extraterrestrial topic has also led, via many twists and turns, to the global warming theory - which is why he chose the title.

He also points out many examples of theories that were widely believed to be true but eventually have been discredited. The goal is to demonstrate that the record of "consensus" in science is pretty poor. One such an example is the so-called nuclear winter and similar predictions that nothing would grow in Hiroshima 75 years after the nuclear attack; the reality was that watermelons were grown there already in the following year.

Other examples he examines, such as puerperal fever, pellagra, and continental drift, are examples of traditionalists holding onto a "scientific consensus" instead of doing real science. The "consensus" believed that pellagra was caused by a germ, and on the contrary puerperal fever was not. The truth was just the opposite and its advocates could not convince others that they were right.

Another example is Wegener's theory of continental drift that claimed that the continents used to be connected to a single pre-continent. Even though every schoolkid can see that his theory was correct (just by observing how Africa and America fit together), his theory has been ridiculed by the "scientific consensus" for 50 years - in fact even 25 years after his death: most geologists simply did not believe that a Wegener-like mechanism could be possible. They thought that there could not be any force that makes the continent "plow".

They were wrong. Although Alfred Wegener could not get all the details straight (he was talking about moving continents, instead of moving plates which also counts the regions of the ocean), all the major ideas - and many details - in his theory of continental drift were correct. In fact, some facts about the mechanism necessary for the continents to move are unknown even today.

He was one individual who was trained in a very different field of science (astronomy and perhaps meteorology) - nevertheless he became the "Darwin of geology" or perhaps "Hubble of geology". He showed that Earth and its map were very far from being static and the different objects (continents) may have come from the same source (supercontinent), much like Darwin did this for the species and Hubble for the Universe. Obviously, the climate scientists have a very hard time to appreciate that one does not have to get an ID that identifies him as a geologist (or climate scientist) in order to become the most important geologist (or climate scientist) of the century.

More generally, Crichton explains that the greatest scientists in history were great exactly because they broke with the consensus in the right way: reproducible and verifiable results of a single scientist are enough. That can't be shocking for a physicist because the history of physics is filled with breakthroughs that were often made by one person, and this person was sometimes ridiculed by the majority. I think that the physicists have a much better understanding of the fact that "consensus science" is an oxymoron - better than the climate scientists, for example, simply because "consensus" is not a scientific argument. (It can only be a sociological pseudo-argument useful for the people who don't follow the subject well, but if a whole culture starts to rely on such sociological pseudo-arguments, the culture ceases to be scientific.) Of course, one of the reasons why the physicists understand these things better is that the truth in physics is much more well-defined.

Crichton recounts the claims about second-hand smoke, about which a federal judge ruled that the U.S. Environmental Protection Agency was "committed to a conclusion before research had begun", and had "disregarded information and made findings on selective information". He recalls that the negative impact of second-hand smoke had been vastly exaggerated.

Crichton points out that it is unacceptable to replace honest scientific research and its conclusions by conclusions that are driven by the will to support a specific policy. Sometimes such a mixture of science and policy may "look" desirable, but more in average we get various Holocausts, eugenics, lysenkoisms, and so forth.

He recounts dire predictions about the environment which never came to pass due to technological advances no one had foreseen. For example, in the 1960s Paul R. Ehrlich predicted mass starvation by the 1970s. When that didn't happen, he again predicted mass starvation for ten years later; that didn't happen either. He similarly twits Carl Sagan for predicting ecological disaster from the Kuwaiti oil fires (based on computer models of the nuclear winter scenario), and complimenting Sagan's rival on global warming, retired scientist Fred Singer, who predicted wind would sweep away the smoke. When Singer's prediction came to pass, nuclear winter lost credibility in the eyes of the public - and not just the general public. But these apocalyptic theories never die; much like Jehovah's Wittnesses, their advocates just change the doomsday date every time their prediction fails.

Crichton also shares the opinion of Richard Feynman that a blind belief in computer models became a new kind of disease.

He also explains that it is completely irrational to predict which problems will be important in 2100, much like it would be ludicrous to buy a stock that is claimed to be profittable in 2100, especially from a person who can't predict what will happen tomorrow (like with the weather). To substantiate his point, he considers hypothetical people in 1900 who are trying to predict the problems that would become important in 2000 - this is a gedanken experiment that I always liked to make when I argued that it is nonsense to plan the civilization for more than 30 years into the future.

The people in 1900 did not know the computers, nuclear energy, airplanes - and Crichton enumerates roughly one hundred of discoveries of the 20th century. This portion of his speech had to be very funny, especially because the last 50 entries are abbreviations such as HTML, EEG etc. Consequently, their predictions about 2000 would have been ridiculous: they would worry about a sufficient number of horses in 2000, the questions what to do with all the horseshit, and similar "serious" problems extrapolated from 1900 to 2000.

Within the section about global warming, Crichton asserts:

• "No longer are models judged by how well they reproduce data from the real world."

Crichton also investigates some postmodernist claims that science is just another tool to gain a political power. He argues that in the case of the global climate, this statement is unfortunately less absurd than what would be appropriate. Well, it's because science is not done properly. To prove his point, he shows that the "mainstream" scientific community behaved much like the Catholic Church during the Inquisition in the case of Bjorn Lomborg and his book The Skeptical Environmentalist. Suddenly it was not necessary to justify the criticism of Lomborg by rational arguments. Crichton was disappointed to learn that the Scientific American played the role of mother Church in the case against the "heretic" Lomborg.

Finally, Crichton proposes possible policies to save science and separate it from politics once again. The scientists should be paid by an agency that is funded by the corporations, the government, as well as the individuals - so that no one knows who funds him. The same experiments should be normally done at least by two groups. And finally, there should be different teams that propose an experiment; teams that perform it; and other teams that evaluate it.

Well, that's a great idea, but I'm afraid that if this climate science is gonna be done with the same people with the same bias, the organizational changes won't improve too much.

#### snail feedback (51) :

Predictability, has to have some pre-set ideas in which it would like to express.

Probability 1, by Amir D. Aczel, page 99,

In 1994 Allan Hills 84001 was handed over to David Mckay of Nasa's Johnson Space Center. Mckay asembled a nine-member team including scientists at NASA, Stanford University, the Universty of Georgia, and McGill University in Montreal. The team endeavored to determine whether there were any signs of life on the meteorite.Would such ideas move the mind to consider the journey's to Mars and explore further, and realize that we had be limited in our views, and now, we are there?

Some just may see the fact that we have a robot working for us, but before that robot came into existance, it has some motivation factor the moves the mind to consider grander things?

The question was then the basis of life on other planets, and we started off with small things you see?

I think that Michael Crichton is probably a very smart guy who became so rich and famous at an early age rhat he found people would listen to him even when he didn't make any sense.

Crichton - N=N*fp ne fl fi fc fL [where N is the number of stars in the Milky Way galaxy; fp is the fraction
with planets; ne is the number of planets per star capable of supporting
life; fl is the fraction of planets where life evolves; fi is the fraction
where intelligent life evolves; and fc is the fraction that communicates;
and fL is the fraction of the planet's life during which the communicating
civilizations live.]
This serious-looking equation gave SETI a serious footing as a legitimate
intellectual inquiry. The problem, of course, is that none of the terms can
be known, and most cannot even be estimated...
Pedantry first: this equation has only one term, there are several factors. N is known rather accurately. We are rapidly closing in on fp and ne is also getting closer to solution. The other factors are currently poorly known. The point of an equation like Drake's is not to predict the number of ET's, it's to break the problem of estimating that number into more manageable components. We can certainly make plausible guesses at some of the other factors, but some may remain unknown unless and until we find another civilization communicating with us. If we discover other life in our solar system we will obviously learn a great deal about fl. Also, better understanding of the origin of life on earth will will clarify that factor. We only have one data point for each of the last three factors - not much but better than nothing. In summary, some of the terms in the equation are known fairly well and there is at least a plausible estimate for each of the others.

The next several paragraphs are nonsense of the sheerest sort. Essentially he is asserting that searching for something we haven't found (yet!) can't be science! So forget that Higgs and LSP guys, the LHC is religion not science. The case would be even more persuasive against string theory.

He is equally full of crap on the subject of nuclear winter. The point is not tropospheric dust - rain efficiently cleanses the troposphere. That is not the case with stratospheric dust. Few fires are hot enough to loft dust into the stratosphere, but large volcanic exposions do and so do thermonuclear blasts. The global cooling effects of the resulting stratospheric dust are well documented in the cases of the largest volcanic eruptions, and we also know a lot about how much dust is lofted by thermonuclear blasts.

I'm afraid you have just convinced me that Crichton is the sort of bright idiot who finds a few things supporting some prejudice of his and then runs with it. This is Ok if your trade is writing science fiction. For science it doesn't work. Too bad he didn't give his Tech speech when Feynman and Gell-Mann were there. The execution might have been amusing.

This comment has been removed by a blog administrator.

One more gem from Crichton: This fascination with computer models is something I understand very well.
Richard Feynmann called it a disease.
What a twisted distortion. Feynman was referring to a guy who got distracted from his job of running the nuclear explosion computer models at Los Alamos by the temptation to play with the computer.

Incidentally, I'm not defending nuclear winter - I'm just arguing that Crichton's critique is crap, as is the supposed link he draws from Drake to global warming.

There are probably three cardinal facts about global warming:

1) Anthropogenic CO2 is accumulating in the atmosphere, and, other things being equal, it would cause warming via the so-called greenhouse effect.

2) The Earth has shown a warming trend, most markedly over the last 15 years or so.

3) The Earth has had very hot and cold spells in the past (almost certainly not anthopogenic in origin).

These facts are a prerequisite for any debate - if you don't know about them, and at least some of the evidence on which they are based, you don't know enough to be worth discussing the issues with.

reader Luboš Motl said...

Dear capitalist,

concerning your pedantry: Crichton may have used the word "term" in a non-mathematical sense.

Now the Drake equation. The only thing I would agree with is that we can estimate the number of stars in our galaxy. Crichton does not write that we can't estimate anything: he says that we don't know any of the factors, and we can't estimate most of them.

As far as I know, your statement that we know the percentage of stars with planets is not correct, and your statement that we know the percentage of the planets that can support life is a complete science fiction. What is then the percentage if you think that we know it? It can still be more or less any number between 0 and 1. What are you talking about?

Even if you thought that you understood the origin of life on Earth, all these estimates will be rather wild conjectures until - possibly - we will be able to count a statistically significant number of civilizations in the rest of the Universe, which I don't expact too soon. ;-) All these things are just pure prejudice. There can be 1 living planet in the visible Universe - and even this can be an extreme luck that there is at least one - and on the other hand, several percent of the stars may have a living civilization around them. It's just a completely unknown thing, and who says that it has been mastered and answered by science is a crackpot.

I have certainly missed the statements that a scientist cannot be searching for new things. Could you be more specific where you saw this quote in Crichton's speech? You know very well that the mathematically oriented science is not what he talks about: he talks about science that claims that it has learned something that should be used for policymaking. If someone wanted to make a policy and consume a fraction of the world's GDP based on a theory assuming the LSP, I would probably also disagreed with that person.

I agree that we know now something about the dust caused by a nuclear explosion; but what we know certainly does not seem to justify the theories that you seem to advocate. It's useless to comment on your personal insults against Crichton. Once again, very generally, the very idea that something is gonna cause an undealable, cataclysmic disaster is a stupidity in 99.999% of cases I've heard of.

Best
Lubos

reader Luboš Motl said...

I've erased a 2-line comment of an anonymous childish moron who was happy that he or she had seen the word "idiot" somewhere and wanted to share his or her happiness. I will keep on erasing comments whose author's estimated IQ is below 70.

reader Luboš Motl said...

Dear pig,

your specific composition of the three "prerequisites" is just a manifestation of dogmatism from someone who apparently wants to memorize scholastic slogans without understanding and analyzing them in depth, and who expects the same from others. What does lead you to believe that these are the three most important things?

One may create hundreds of observations, arguments and pseudoarguments with the same quality and importance as yours, for example:

1. The Earth showed a cooling trend between 1940 and 1970 when the heavy industry expanded most, and most markedly between 1400 and 1800.

2. The production of aerosoles cools the atmosphere, and it's very important. (One can replace the aerosoles by virtually anything that appears in the atmosphere and claim that it is the critical thing - vapors, radiowaves whose concentration jumped by many orders of magnitude, various chemicals, anything.)

3. The continents are moving and Sahara used to be on the Southern pole, for example, which drastically affects the climate. Alternatively, the climate is dictated by the earthquakes and floods and their the primary things to be studied.

4. Solar activity is known to affect the Earth's climate in the very long term.

There are thousands of facts that are more or less important, and if someone starts to selectively emphasize some of them, he's not doing proper science. Why do you talk about "warming" in the last 15 years and not the cooling in 1940-1970? What do you intend to get out of this completely unscientific selection process of data?

Why do you neglect all other gases except for CO2 whose relative concentration is like 400 parts per million?

What you're showing is non-scientific dogmatism EXACTLY because you don't want to allow some assumptions to be questioned - and you want to humiliate everyone who questions them - everyone who asks some questions. You don't want anyone to question the dogma that CO2 is the most important part of the atmosphere that should be studied. You don't want anyone to question that it is more important what the graphs show in the last 15 years as opposed to the previous 30 years. You don't want anyone to ask the fundamental questions, and therefore your approach is an example of religious dogmatism but not science.

Best
Lubos

reader Luboš Motl said...

And yes, the computer models. One can read what Feynman really wrote at

http://members.cruzio.com/~arlo/Feynman_on_Computers.html

Mr. Frankel started to suffer from that disease, switching things back and forth etc.

That's a disease that some climate people also suffer from: they play with the models instead of focusing on the questions they should answer.

Of course that the people who are playing with these models won't agree that they're much like Mr. Frankel - that they're just playing games.

If one does not have a meaningful theory that controls the atmosphere predictably - and obviously such a theory is not good today since people can't predict weather for tomorrow - then running models that pretend to predict the next 50 years is just a stupid computer game.

http://images.ucomics.com/comics/ta/2004/ta041229.gif

reader Luboš Motl said...

Well, the guy on the cartoon is definitely correct if he talks about this particular fiction and this particular science.

Re: plate tectonics - as a kid, I had had an old copy of George Gamow's "The Biography of the Earth", and that book expounded on the theory of continental drift. So, later on in life, I was surprised to read that at one time this was a controversial theory. Looking around now, I find that Gamow's book was first published in 1941, and there is at least a 1959 edition, which perhaps is the one I had. The web also says that continental drift began to be accepted by geologists only around 1961/62.

Does anyone recall the book? Did Gamow change the book between editions or was he a plate tectonics guy from the start? If the 1941 edition of his book had this, then what were his reasons for accepting what we are told was an unfashionable theory?

-Arun

Lumo said - your specific composition of the three "prerequisites" is just a manifestation of dogmatism from someone who apparently wants to memorize scholastic slogans without understanding and analyzing them in depth, and who expects the same from others. What does lead you to believe that these are the three most important things?I'll ignore the insult since I'm actually a very undogmatic (as well as tolerant) person. I mentioned those three facts because they have good experimental support. If you were paying attention, you would have noticed that they hardly make any case for human caused global warming and none for catastrophic predictions.

CO2 is important because it's (currently) the second most important greenhouse gas, and because it has been measured carefully for a long period and we can closely correlate the increases with anthropogenic sources.

The continental drift events you cite are very slow. The Earth has had many extremely hot and cold periods with the continents in essentially their current positions. The Sun may have some effect on climate, but it's rather striking how slim the evidence for it is. There may be some correlation with long term sunspot periods. One of the more startling aspects of our world is how constant the planet's temperature has remained despite the steady increase in size and radiance of the Sun over the past 4 billion years or so.

About continental drift: Geologists could see the Africa-America fit, but they were suspicious of Wegneners idea because they knew his proposed mechanism (Continents sliding across the rigid oceanic crust) violated the laws of physics. It was only after the discoveries of the 1950s and 60s (Young oceanic crust, subduction, and creation of oceanic crust at mid-ocean ridges) that a workable mechanism could be found. String theorists used to think our universe had 26 dimensions, then ten, and now eleven. Because string theory is a religion or because it's an evolving science?

More later if I get the chance.

Cheers,

Pig

reader Luboš Motl said...

Hi Capitalist!

First. Importance of Greenhouse gases. The most important greenhouse gas is believed to be water vapor. Its percentage on the "effect" is between 30 and 80 percent - it is almost completely unknown what the percentage is. I can give you evidence that it is unknown. PBS/NOVA argued that it is 70 percent or more, for example.

The #1 reason why no one focuses on water even though it is the #1 greenhouse gas is that water vapor is not correlated with the corporations and capitalism. Only the #2 reason why no one is interested in water is that no one wants to question that it rather quickly returns to equilibrium. No one wants to question it because of the reason #1.

CO2 is different.

Now, CO2's percentage on the greenhouse effect is uncertain, as follows from the above comment on H2O. By very naive assumptions, one can believe that it takes centuries for CO2 to disappear. I say it's naive because there are CO2 sinks - the ocean surface and the forests.

It is not hard to believe the article in Science 1998 that experimentally measured

http://www.ncpa.org/hotlines/global/pd11498f.html

that higher concentrations of CO2 are among the reasons that stimulate the growth. The particular authors deduce that North America is a CO2 sink if you sum up everything. In 2050 the forests are expected to grow by 25 percent faster than today, which cuts the CO2 concentration increases themselves.

What I want to emphasize is that it's mostly unknown how much CO2 is absorbed and where and how much is emitted. If forests burn, for example, they become CO2 sources. There is no doubt a huge amount of CO2 being both emitted as well as absorbed - it's like the forex market, if you wish. A trillion of dollars sold every day, and some small inbalances imply slightly changing rates. And one must carefully count all the effects in both ways, and study their mutual relations, and the result is just extremely uncertain.

If someone works with a model with a stable amount of CO2 only, nothing else, and calculates the effect on temperature, it's as stupid as taking the quarks' contributions to the QCD beta function and arguing that because it's positive, the total is most likely positive. It's just a random guess. One must be able to keep more or less all these possibly relevant things under control if she wants to make any statements. If she has 1/3 of the effects under control, it's certainly not good enough. The probability that the answer has a wrong sign is about 50%.

"CO2 is important because it's (currently) the second most important greenhouse gas, and because it has been measured carefully for a long period and we can closely correlate the increases with anthropogenic sources."

Even this is incorrect. There has already been much more CO2 in the atmosphere a long time ago. You can't just say that something is "due to anthropogenic activity". We are living on this planet and we shaped how many forests there are, and so forth. Will you count the smaller number of forests (as compared to 10,000 years ago when people started to cut the trees) as a current anthropogenic influence? No doubt, in this sense many things are anthropogenic. But such adjective is totally irrelevant. Only the rats and trees pretending that they are humans, but in reality wanting to eliminate human civilization, like those in the Wildlands project

http://www.twp.org/

could think that this being "anthropogenic" is wrong or something that should be undone.

The evidence for the solar influences on the terrestrial climate is comparable to the evidence that the climate depends on human produced CO2, to say the least.

Concerning the continental drift and dimension of string theory.

Even in the string theory case, what you say sounds nuts to me. Of course that if someone ever believed that this real Universe around was described by the 26-dimensional theory and if he insisted on the number 26, he was just wrong, much like the critics of Wegener were wrong.

We know believe that the total number of dimensions is 10 or 11 - although the precise definition of the number of small dimensions is a subtle thing. But if we happen to be proved wrong in the future, we are just wrong. There is no way to justify being wrong by "evolving science".

I don't understand what you think is the difference between your interpretation of "evolving science" and "replacing wrong statements by (more) correct statements". Superstring theory is a better offspring of bosonic string theory, but as long as we judge the validity of the statement "the spacetime around us is 26-dimensional", it's simply a WRONG statement. It always was, and anyone who insisted on this statement was incorrect.

In the same way, the people who argued that there could be no mechanism compatible with physics that justifies Wegener's picture of the history of continents - these people were WRONG once again. There is just no way how can you make them "correct" or "evolving". They are not connected continuously to anything correct. They are not a simplified version of the truth: Wegener is the simplified version of the truth - his critics were just simplified versions of dogmatic morons.

Once again: their guess that the laws of physics were incompatible with Wegener's statements were just wrong statements. I don't know how else can you ever summarize this very simple situation.

Wegener may have believed that the boundaries of the "plates", using the current language, were at the beaches. But it does not affect the mechanism. According to plate tectonics today, it could also happen that the plates looked like that - there's just no very good reason for it, so it's unlikely. The plates' boundaries usually cross the ocean.

OK, but assume that the plates end at the coasts. Then what Wegener was saying is kind of literally true even according to the current theories. The plates are "plowing" through the ocean plates. The hard part of it is near the destructive rift - the plate must either insert itself under the other, or something else must happen. They "plow" there. The easy part is on the other side of the continent where you're creating "empty space".

Wegener just did not know exactly which parts of the crusts were soft and which were hard, but nevertheless the outcome looks almost identical to his thinking. He also did not know the exact force that pushes the continents. We don't know it too well even today. The plates are floating on some softer material that can have currents in it, driven by temperature inbalances or whatever. We don't know what's there exactly and how to calculate these forces that push the plates. But the statement that no force can move the continents and force them to "dig" through the crust - it's just a WRONG statement, and it has always been.

You know, before Wegener, the people believed that the continents were static and the similarities between the animals in South America and Africa resulted from "natural bridges" that used to connect the continents but they sank under the ocean afterwards. This was not an approximate version of the truth. This was simply a wrong, unusable theory. Nothing from it survived. It was like creationism for the species. I am shocked that someone can advocate it today and criticize the revolutionary named Wegener - it's just like defending creationism.

If someone says the magic words "I think it is incompatible with the laws of physics", it does not mean that he is immediately correct or approximately correct just because he used the powerful ally "physics" in his sentence. These guys were just wrong. Real physics says that they were wrong. The people who argued that it was impossible to construct airplanes - or anything that flies and is heavier than the air - were also wrong. Their statement that physics did not allow it was just evidence of their poor knowledge of physics. One can explain why the knowledge was poor and why they had various prejudices, but these explanations can't make them correct. I have no idea how can you label it as "evolving science". Yes, it was evolving from wrong theories to (more) correct theories. Wegener's was the correct theory, and his critics' picture was the wrong one.

You know, Lord Kelvin or who was that calculated that the Sun had to be young because it burns out quickly. It was a good piece of work - as a toy model for future, more correct calculations - but it was a completely wrong conclusion because it was based on wrong assumptions about physics (neglecting nuclear energy). Darwin was better and he knew that the Sun had to be billions years old.

But if we talk about the question what is the age of the Sun, you can't say that our current answer is an evolved version of Kelvin's estimate. Our current answer is a confirmation of Darwin's estimate.

You seem to have problems to distinguish the truth from someone, who is wrong, saying "I am right".

Best
Lubos

reader Luboš Motl said...

Incidentally, concerning water, there's evidence that the concentration of water has increased as well in the 20th century. Given the fact that it is claimed, even by the greenhouse advocates, that water is a more important greenhouse gas than CO2, one should ask the question why no one makes much ado about water vapors.

Once again, the answer is that water is not a politically powerful tool. You can't punish Exxon or Bush by this argument because they don't seem to emit too much water vapor. All these things are politics. The people try to make statements about the gases that can have political impact.

Crichton -SETI is unquestionably a religion. Faith is
defined as the firm belief in something for which there is no proof.
This is the type of statement I had in mind when I said Crichton criticizes searching for things not known to exist. SETI stands for the Search for Extraterrestial Intelligence. Searching for something whose existence is yet to be shown is not neccessarilly religion. If we commit several billions of Euros to the search for the Higgs and an LSP, it seems hardly a bigger reach than committing a few hundreds of thousands to SETI.

Everybody searching for ETI knows the search has a lot of unknowns - that doesn't make the search a religion. I don't say we know all these numbers,I say we are beginning to pin down, for example, the fraction of stars with planets because we have now found planets around a couple of dozen nearby stars. This is very strong evidence that a large fraction of stars have planets. We don't know much about what fraction of these are habitable, because our techniques are not yet sensitive enough to find Earth sized planets. That is likely to change as our methods improve.

Also, please stop accusing me of fanatical beliefs I don't hold. I don't know how strong the evidence for a possible nuclear winter is, but I know that the troposhperic dust cited by Crichton is largely irrelevant. I am also agnostic about the potentially catastrophic effects of global warming, but I've seen a steady increase in the evidence for its reality and potentially serious consequences.

Crichton's supposed theme is a rant against "consensus science." I find it pretty ironic that you, Lubos, who have devoted so much time and vitriol to denouncing any who would stray from the stringy consensus, would buy into this. Scientists, if they are honest, try to make their best judgement. Scientific theories get support and funding when enough other scientists start believing in them.

Lord Rayleigh calculated that the Earth could not be as old as the geologists said it was because it was still too warm. Was this because he was stupid? On the contrary, it was because he followed theory where it led. New knowledge was needed to bring physics and geology back into consistency (relativity and radioactivity). Many of the supposed "scandals" of "consensus science" are of exactly that form.

Pig,

Re: continental drift - it appears that the geologists had cogent reasons to not accept it. One cannot call that irrational or stupid or close-minded. What it should teach us is that ideas for which there are current good reasons to reject may nevertheless turn out to be right.

Likewise, just as there are self-fulfilling prophecies, there are self-nullifying prophecies. Surely if someone had strongly enough taught that a catastrophic tsunami would kill lots of people in the Indian Ocean, where tsunamis rarely happen (compared to the Pacific) then a warning system might have been put in place, and the death toll would be much smaller.

Anyway, the scientific consensus as a way to do science is one thing; but what does one base public policy on? The nice people at TechCentralStation.com and Lubos and Crichton all want to do away with the scientific consensus as a means of deciding public policy. They suggest no replacement. One possibility is that science should not enter public policy at all. Thus, e.g., one should use tarot cards or divination or such, e.g., to decide how much cod can be fished each year from the North Atlantic in a sustainable manner. The other is to use the best scientific information available, the consensus, with the explicit understanding that the consensus does not represent the truth, it represents a best guess, and if our knowledge changes, the policy changes as well. Finally, the way preferred by TechCentralStation certainly, and others, is that their ideology informs them of the truth, and they have no need of scientific input. The truth of their ideology is shown by science, where applicable, and the falsity of opposing science is proven by the truth of their ideology.

-Arun

reader Luboš Motl said...

Oh, so SETI is what you meant. Are you joking, capitalis? ;-) Do you really think that the existence of the Higgs boson is similar to the existence of the extraterrestrial aliens?

I can't believe that you're serious. The Higgs boson - or something like that - is dictated by the unitarity of the WW WW scattering in the Standard Model, which is an extremely accurately verified theory.

There are very good experimental reasons, combined with a few hours of calculations, to be convinced that something like that must be produced. There are some slightly weaker reasons to be convinced that we should see supersymmetry.

But there absolutely no - neither direct nor indirect - pieces of evidence that there are some aliens. If you think that the statement "there is another civilization in this galaxy" is comparably scientifically justified as the statement "the LHC will probably see a Higgs boson", then you lost your mind.

Once again. Rayleigh was probably not stupid; but he was definitely WRONG with his calculation. I don't know what the word "wrong" should mean else than exactly things like that. Should I say that he had to be correct just because he was a famous scientist, or what? He was WRONG, WRONG, and WRONG, and something is WRONG with you if you can't understand it.

In physics, one cannot just make blind calculations of some kind. One must also have a control over the validity of the theories and assumptions that she uses. This is what he did not master in that particular case, and therefore his conclusion is just wrong. If you wish, it was not only wrong but also partly stupid. But it was more wrong than stupid. ;-)

lumo - retired scientist Fred Singer, who predicted wind would sweep away the smoke.Actually everybody knew wind would transport the smoke - the only question was how fast the atmosphere would remove it - and the answer was pretty fast.

Fred Singer was involved in some important science, but his later career has been devoted to sometimes misguided skepticism. He was famously wrong about the connection between ozone depletion and CFCs.

He sat next to me at a climate conference a few years back and we briefly discussed his book on global warming (I had a copy with me). Most scientists who gave papers hung around and took a lot of questions, but Singer made his speech and disappeared like a shot.

reader Luboš Motl said...

Arun, this is mostly a hypocricy. There was never a too good reason to reject Wegener's theory. One could have rejected a particular theory that the drift was caused by the tidal forces of the Moon, but one certainly should have never rejected the statement that there are some forces that make the continents move.

We did not have to learn QCD before Wegener's theory became meaningful and compatible with our physical laws. Wegener's theory is based on mechanisms that are completely compatible with the physics of the 19th century, and all statements that Wegener's theory had to be incorrect were simply a bad science.

It seems that you tend to justify their lousy assessment of this problem by the fact that there were many people with that stupid opinion. In that case, you're unfair and biased. It does not matter that the number of people who make incorrect conclusions is large. They're still equally wrong.

reader Luboš Motl said...

I've never - ever in my life - argued that string theory is correct because there is scientific consensus about it. You are absolutely misled if you think that I would ever think something like that.

What I've been defending is that the physicists should have the freedom to pursue the ideas that they find likely and important, and everyone should assume that this is what is effectively happening.

But the reasons why I think that string theory is on the right track has absolutely nothing to do with the majority support of the theory between top=bottom high-energy theoretical physicists.

String theory can only be accepted as the right description of the Universe once non-trivial predictions from it are confirmed experimentally. Until that happens, people work on whatever they choose, and my reasons to be convinced that some hypothesis in theoretical physics is correct or incorrect is always based on technical reasons - never sociology.

Otherwise I would be much like the "consensus scientists".

reader Luboš Motl said...

There are many more detailed questions - that go beyond "string theory yes or no" - where I have a minority opinion, and so forth. If someone chooses his or her opinions always to belong to the majority, then he or she is a useless piece of nothing whose opinions are irrelevant shadows of something real. If there is a whole group of people that behaves like that, this group of people has no value for science.

Climate scientists pay attention to CO2 because humans play a significant role in its production (individuals and corporations and governments).

They are also interested in water vapor, because (for one of many important reasons) it's the most prominent greenhouse gas. We have almost no direct control over its presence or distribution in the atmosphere though, so there is not much we can do about it.

About right and wrong in science: I quoted Bohr to you once before, but here it is again. "We theoretical physicists have a big advantage over philosophers, in that each of us has published a paper that was subsequently proved wrong." I suspect that string theory is more like philosophy in that respect, since (unless you make a math error) you can't be proved wrong. If you can understand what a big handicap that is Lubos, then I think you will take a step toward wisdom.

Just for the heck of it I took out Joe Polchinski's book on strings, read pages 5 and 6 (his eight reasons for string theory) and asked myself how many were still believable. My guess was four (there is no evidence for 4 or 5, and 7 and 8 seem just wrong).

reader Luboš Motl said...

"Climate scientists pay attention to CO2 because humans play a significant role in its production (individuals and corporations and governments)."

Jesus Christ, this is precisely one of the reasons why I say that it is a biased junk science. Why should a real scientist selectively focus on human-produced gases as opposed to the naturally present gases? How can one make any conclusions about the whole atmosphere if he openly focuses on a subset of gases that is chosen according to some political criterion? Are you joking, or are you really supporting this approach?

"They are also interested in water vapor, because (for one of many
important reasons) it's the most prominent greenhouse gas. We have almost no direct control over its presence or distribution in the atmosphere though, so there is not much we can do about it."

But you don't follow what science is. Science is not about "what we should do among the things we can do". Science is about explaining how the things work. And for a scientist it is equally interesting to learn how natural systems work as well as artificially produced systems work. One can't understand the greenhouse effect without understanding all greenhouse gases, and water is the #1. Looking at the #2 gas just because it is politically interesting is simply junk science.

Even for an applied scientist, both of these categories - naturally present gases and gases important in human activity - can be equally interesting. Science studies both nature as well as technology and both of them are practically used.

What drives me up the wall is that you repeatedly - and kind of openly - declare that the task for science is to "find some things where we can do something about the environment". But the activity defined by this slogan is not science - it is organized ecoterrorism. Whoever believes that the search for such "tasks where we can do something about something" is what climate science should do, is a politically radical moron - and it does not matter whether she or he is a director of the Intergalactic Panel for Climate Change or anything like that.

Such people have certainly no justification to be present in science, and if I can express my political belief, they should also be eliminated from policymaking.

Another thing.

The idea that something in science cannot be proved wrong is YOUR idea, and it is one of the reasons why your opinions expressed on this blog are completely insane. In real science, one can eventually judge the validity of any scientifically meaningful and sufficiently well-defined statement. This is what distinguishes science from other, less interesting human activities.

The critics of Wegener were wrong - and kind of narrow-minded, from today's perspective. Those who expected that 26 dimensions would be a permanent prediction were also wrong. And so forth, and so forth. It is just you who wants to continue to argue that many clearly falsified hypotheses are still kind of correct. You should be ashamed because your point of view is truly pathetic.

String theory is, of course, a science according to the very standard old-fashioned definition of science, and the wrong statements made by the string theorists are (or will be) eventually proved wrong. But in your optics, it's not just string theory that you consider unfalsifiable: you think that nothing in science should be falsifiable, and you prove this weird point of view repeatedly by your support for various theories that have already been falsified decades ago.

Best
Lubos

I am sorry, Lubos, but if someone had cogent and rational reasons to doubt Wegener's theory, then that someone was not narrow-minded or biased or stupid.

Anyway, here is what one lecturer says (and it goes against the notion that Wegener was ridiculed)

"Wegener's hypothesis brought down a storm of controversy because it challenged established scientific wisdom. The prevailing view of the Earth was based on continuity of geological processes and on the permanence of major surface features such as continents and ocean basins. Wegener's concept of drifting continents was a radical departure in thought for the geological community.

In spite of this, the idea was not simply dismissed as a crackpot notion. Though not a geologist, Wegener was an established scientist, a German meteorologist and polar explorer. Furthermore, he had done his homework. He marshaled evidence in support of his idea from a wide variety of sources, the bulk of which was drawn from publications of respected geologists.

....

There continued to be many other arguments, pro and con. In the middle 1920s, two important conferences were held -- one in London, the other in New York. Wegener was invited to defend his ideas and did so with great persuasion.

Even so, at the end of the London conference, two of his critics expressed what seemed to be the majority view:

* In examining ideas so novel as those of Wegener, it is not easy to avoid bias. A moving continent is as strange to us as a moving Earth was to our ancestors, and we may be as prejudiced as they were. On the other hand, if continents have moved many former difficulties disappear, and we may be tempted to forget the difficulties of the theory itself and the imperfection of the evidence...

and:

* We are discussing his hypothesis seriously because we should like him to be right, and yet I am afraid we have to conclude...that in essential points he is wrong. But the underlying idea may yet bear better fruit.

After the American conference, which went even more poorly for Wegener, the idea of drifting continents passed into an oblivion that was to last for over 25 years.

(http://mac01.eps.pitt.edu/harbbook/c_iii/chap03.html)

continuing,
http://mac01.eps.pitt.edu/harbbook/c_iii/chapter_3c.htm

If you compare Figures 3-29 to 3-32 with Figure 3-1, you will see that Wegener certainly had the right general idea in his continental reconstructions. So why was he repudiated by the scientific community in the 1920s?

In the first place, Wegener was unable to provide a convincing mechanism for moving the plates. It is important to recognize that Wegener did not come up with an early version of plate tectonics -- his theory was concerned only with the drifting of the continents. For him the ocean floor was a stationary impediment rather than the most mobile part of the whole scheme. In Wegener's day, the floor of the ocean was virtually unknown to scientists. Recall that in science, that theory is best which best explains all available observations. The emergence of plate tectonic theory was based largely on observations in paleomagnetism, oceanography and seismology that were not available to Wegener.

Most of Wegener's arguments were based on paleontology and paleoclimatology -- two of the better developed sciences of his time. His detractors, however, were able to propose alternative theories that did not violate the entrenched belief in the permanence of the oceans and continents. Temporary land bridges that have since sunk beneath the waves, or natural rafts of floating vegetation, had allowed creatures to migrate from one continent to another across the vast oceans, they said. And everyone knew that past climates were very different from those of today. Wegener's genius lay in his ability to draw correct inferences from circumstantial and often scanty evidence. But the scientific community was under no obligation to accept his inferences when the weight of the available evidence was not decisively in his favor. There is also a natural reluctance to discard familiar and long-established ideas that have proved useful in one's career. Scientists are human, too.

Nonetheless, once the necessary observations became available, the scientific community made an abrupt about-face, revived Wegener's idea of drifting continents and quickly transformed it into the theory of plate tectonics. Three independent developments in the fifteen years following the Second World War set the stage for the revival. The U.S. Navy, idled by the end of the war but impressed by the capabilities of submarine warfare, supported the monumental task of mapping the ocean floor throughout the world. Seismologists were amassing data on the distribution of earthquakes and the behavior of earthquake waves in the upper mantle, aided by fledgling new devices called computers. And a few scientists in England, Japan, France, and the United States were pursuing studies aimed at working out the history of the Earth's magnetic field.

In its early days, paleomagnetism must have seemed a very esoteric science. With no application in sight, scientists were simply pursuing their own curiosity about the origin and behavior of the magnetic field.

Oceanography had become a burgeoning science. By the mid 1950s the continuity of the worldwide oceanic ridge system had been established. By 1961 ocean-floor maps had become available and data showing the striped magnetic patterns associated with the oceanic ridges saw publication. A correct explanation for the magnetic stripes actually appeared in print as early as 1963, but was largely ignored. The evidence for both sea-floor spreading and magnetic reversals was considered very inconclusive by most geologists at that time. But the evidence for continental drift and sea-floor spreading mounted.

By 1966, the worldwide occurrence of magnetic field reversals had been confirmed and a computer-drawn reassembly of the continents bordering the Atlantic into a Pangea configuration showed that the continental shapes really did fit together very well. The concept of the transform fault was introduced. Using seismic evidence, subduction was demonstrated in the Tonga Trench in the South Pacific.

Now the pace accelerated and, like a large and difficult jigsaw puzzle that mostly has gone together slowly and painfully, the last few pieces went together in a rush. Three of the key pieces were the discoveries of sea-floor spreading and subduction, and the recognition of the distinction between the lithosphere and the asthenosphere based on seismic studies. By 1968, the essentials of plate tectonic theory had been worked out in a series of papers by two dozen or so scientists of half a dozen nationalities. Unlike the theory of continental drift, which was clearly Wegener's, there is no one name associated with plate tectonics. It was a truly international and interdisciplinary effort.

In order to concentrate on the concepts themselves, we have not listed any of these scientists here, but instead refer you to the three books by Sullivan, Marvin, and Glen, cited early in this unit. The complete story is interesting, exciting, and very human, and we earnestly recommend it to you.

---------------------

This does not sound like the story Crichton narrates.

OK, you have caught in sort of a mistatement.

Pig - "Climate scientists pay attention to CO2 because humans play a significant role in its production (individuals and corporations and governments)."

Lumo: Jesus Christ, this is precisely one of the reasons why I say that it is a biased junk science.

Scientifically, of course all green house gases are interesting. From a policy standpoint though, the interesting things are things we can potentially affect. If your car is headed off a cliff, the brakes and steering wheel are more interesting than the windshield wipers and headlights.

You totally misconstrue my ideas about truth, falsity, and falsifiability in science. My point is that scientists can get wrong answers for lots of reasons besides confusing science with religion. Geologists weren't practicing religion when they doubted Wegner, they were trying to take some pretty important facts into account. Ditto Lord Rayleigh. In each case, the scientists got wrong answers because they were missing important facts - facts that were not learned until decades later.

Crichton seems to me to be saying that the cited scientists who got wrong answers were victims of some sort of mass hysteria. In many cases it seems to me that the real problem was that the relevant facts were not yet in.

Arun on continental drift - very helpful and informative. You make the points I was trying to make with more clarity and especially with more data!

Hi Lubos,

Water vapour is very important greenhous gas but it's life cycle is very short. Come monsoon, it'll become rain. However, life cycle of CO2 in the environment is very long. It takes thousands of years for CO2 to become marble. So, gases like CO2 play backup role for water vapour. Increase of CO2 level increases the average temperature of the atmosphere. This increase in temperature in turn stops some of the water vapour from condensing during night/monsoon/winter. Now this water vapour will cause more greenhouse effect.

But if you were to somehow remove some CO2 from the atmosphere even after extra water vapour has built up, the excess water vapour will gradually condense during night/monsoon/winter.

So water vapour is rather unimportant without talking about CO2.

The previous comment was by as.

-as

This comment has been removed by a blog administrator.

This comment has been removed by a blog administrator.

reader Luboš Motl said...

Arun: the stories from the history of Wegener's ideas are absolutely OK with me - I've read many of them - but your way of interpreting them is incredible.

You know, science is about explaining how the world works. It's about reality. It's not about impressing some misled people on some conference. You probably care about statements like "this conference went even worse for Wegener...". But today we kind of know that he was right and they were wrong, and the more revolutionary and hard to accept his theory was, the more his scientific contribution is rated. It's exactly how one recognizes the great contributions to science.

I have no idea how can you call today their prejudices "cogent reasons". In science, it's the experiments and observations that decide whether something is cogent or not. Their ideas were only convincing for people who did not have the right ideas and right feelings for the principles that are fundamental in geology today. What's cogent about these wrong people? Is creationism cogent? Are they cogent because the number of these misled people was large?? You could then also argue that China and India with their religions and large populations have cogent picture of the cutting edge science.

The fact whether the ocean is a static plate or just another moving plate does not affect the plausibility of his pictures, almost at all. All these justifications are just inventions of scientists who were wrong about a very big question and who wanted to marginalize how much wrong they were. Wegener's arguments were based on paleoclimatology and paleontology which were the most reliable and best understood fields at that time. It's the right approach to build your theories on things that are best understood. If someone is building his opinions about the continents on something that is poorly understood, then he's doing science incorrectly.

I think that you find this story inconvenient - and you can't resist attacking Crichton for which act there is absolutely no justification. You feel threatened simply because you REALLY believe that if there is a majority backing some scientific opinion, it is more likely to be a correct and "cogent" scientific opinion. But this opinion is pseudoscience and stupidity. It's the same pseudoscience that killed 6 million Jews during the holocaust because they were consensually believed to be the inferior race. The same pseudoscience that installed communism in the Eastern Europe for roughly 50 years because the consensus at that time was that Marx and Lenin analyzed capitalism right. The same pseudoscience that is today applied to humiliate global warming skeptics. The record of this consensus-driven politicized pseudoscience is pretty bad.

reader Luboš Motl said...

Do you have some problem with your brain, pig? You write:

"Scientifically, of course all green house gases are interesting. From a policy standpoint though, the interesting things are things we can potentially affect."

That's what I say, too. They emphasize CO2 because it is more interesting for their policies. It has political reasons. Understanding of water vapor is more important for science and the truth because water forms a higher influence on the actual greenhouse effect on this planet. They don't want to study it as carefully as CO2 - or not at all - which is why they don't study the actual science of climate but instead, they're doing dirty politicized pseudoscience that is meant to support general policies that were designed already previously - namely suppressing capitalism, corporations, production, and human activity. And you're a part of this disgraceful political game, Arun and Pig!

I always knew that as far as the average society goes, we're not in a scientific age yet. Crichton made a great job because without him I would not understand how bad the situation actually is.

reader Luboš Motl said...

I've erased roughly two anonymous 2-line content-free comments.

Lubos,

a. Wegener was right on scanty evidence, and yes, that makes his contribution great.

b. Wegener's evidence was scanty. Let us compare the situation to Arp's anomalous redshift observations. In any one of these, there is a galaxy at relative low redshift and one or more quasars with a high redshift, and a seeming physical connection via gaseous filaments extending from the galaxy and surrounding the position of the quasar, and these filaments have an intermediate redshift. If there is indeed a physical connection between the quasar and galaxy then redshifts of quasars are not cosmological in origin. Now Arp has observations, but no physical mechanism, and the standard model can accomodate these observations, roughly - improbable juxtapositions will be observed in a large enough universe.

c. Likewise, with no mechanism available to explain what makes the continents move (granite continents plowing through basalt ocean beds has its own problems), the scientists were justified in their skepticism. Do look around, there are many amazing coincidences and strong correlations out there; we recognize them as accidental because we have no physical mechanism for them.

d. The point of bringing up the conference is that it was not a bunch of hysterical naysayers that rejected Wegener's continental drift. Rather, they really liked the idea; but simply could not see how to make it work. Even Wegener could not figure out how to make it work as a physical model.

e. It was Lord Kelvin, not Lord Rayleigh, who computed the age of the earth based on its cooling rate and found it to be some tens of millions of years. There we know that he had an ulterior motive, to preserve the Biblical account and to rule out the long time scale needed for Darwin's evolution. Nevertheless, it was a sound physical argument, and the discrepancy between the physical and geological time scales remained until the discovery of radioactivity; and Kelvin promptly abandoned his argument.

f. I'm wasting time on this blog.

reader Luboš Motl said...

a. Not exactly. The importance of Wegener's contribution is not measured by the allegedly small amount of evidence, but rather by the difficulty other people had to switch to his mode of thinking.

b. Wegener's evidence was a union of many powerful and very diverse arguments - in fact, a significant fraction of the evidence we have today. Wegener knew not only that Africa "fits" to Southern America: he collected geological evidence showing appropriately equivalent types of rocks - evidence that the continents were connected - much like the fossils of the same animal species that were found at the corresponding places - much like the known observations that Sahara used have arctic climate, and several others. He figured out what's the correct interpretation of the observational facts, and he knew that the extension of his theory would also naturally explain earthquakes, volcanos, and formation of (some) mountains and therefore it had a powerful "unification" strength. Describing the exact physical theory of the drift is an independent task.

Arp. I think he knows much more about the numbers, redshifts, brightness than most other astronomers, and he has some feel for the probability that his observed regularities between the redshifts appears as a coincidence. What he has is a possibly legitimate observation, not a complete theory, but in my opinion it is not much more than dogmatism if someone is anything else than open-minded. Such a possible loophole that he could be revealing could only affect our understanding of quasars - our idea about the origin of their redshift and their structure in general - but it could also turn out to have more far-reaching consequences. I think that Arp's case is weaker than Wegener's simply because he only has one type of observation. If he could simultaneously explain 5 more types of "coincidences" and possible "anomalies", my estimated probability could grow above 50 percent. These are observations - I see no way how can someone ignore them. I am not a *complete* ignorant about cosmology, but I can't give you a convincing proof that we understand quasars properly.

c. Scientists are always justified to be skeptical, but being skeptical does not guarantee that they are correct, much like being non-skeptical does not guarantee that someone is correct. In Wegener's case, your counting of "coincidence" was simply incorrect. Today, when the prejudices are gone, we know it. The evidence Wegener had would be just too much of a coincidence. There has never been an argument that the continental drift was impossible according to the laws of physics and your justification of the skepticism is not too powerful. Wegener did not claim that he had a *satisfactory* physics computation of the drift forces: he claimed that he had a correct interpretation of many kinds of the observed data and that there had to exist a mechanism behind his picture of paleogeology. And he was right.

Wegener knew very well that he had not have a working physical mechanism, and he always admitted it. For example, in the 4th revised edition of Die Entstehung der Kontinente und Ozeane (The Origin of Continents and Oceans) Wegener states that "the Newton of drift theory has not yet appeared. His absence need cause no anxiety; the theory is still young ..."

d. Of course that many of them were hysterical naysayers. Just make a search for Wegener+ridiculed at Google, or Wegener+dismissive. It was roughly as hysterical as the humiliation and hysteria today against e.g. Bjorn Lomborg. For example, open

http://www.es.flinders.edu.au/~mattom/science+society/lectures/lecture31.html

You will read "But the lack of a mechanism cannot explain the hostility of most geologists, who pointed out Wegener's lack of formal geological training [that's what happens with Lomborg and others as well] and ridiculed his work." Of course, I completely agree with that. They did not have any rational argument against his theory. It was just an argument of brute force.

Much of the anti-Wegener hostility is listed at

http://www.es.flinders.edu.au/~mattom/science+society/lectures/illustrations/lecture31/hostility.html

Wegener's answer - e.g. to his father-in-law - was very apt, I would say:

"Professor P.'s letter is typical! He will not allow himself to be taught. Those people who insist in treating only with the facts and want nothing to do with hypothesis, themselves are utilizing a false hypothesis without appreciating it! ... there is nothing in his letter about the struggle to get to the bottom of things, but only about the pleasure of exposing the limitations of other men."

e. I know it was Lord Kelvin, and I was writing about Kelvin. Rayleigh was introduced by Capitalist Pig, and I only used his proposed name to make him happier. ;-)

f. So am I.

Arun & Lumo - My apologies for confusing Rayleigh and Kelvin. All those limey lords look alike to me.

Shouldn't you guys be working on solving the mysteries of the Universe or at least at getting tenure?

Although I agree with Lubos about the dogmatism of the socalled consensus science, I can cite an example where scientists were wrong, but were justified in being wrong.

Hubble's law in its initial incarnation was NOT taken seriously by the consensus of scientists. And you know what, I would have been one of them.

His data at the time was off by a factor of four or so (mostly systematic error), and it did not support the claim for anything but a steady state universe. Couple to that, the fact that a steady state universe seemed to be the simplest explanation (to the untrained minds of the time), and I think people were justified in rejecting a big bang universe.

OK, hindsight 20/20 Olbers paradox and the like were severe theoretical problems, but back then I think I might have been inclined to agree with the available data of the time and reject the correct viewpoint of the world.

-Haelfix

I stumbled onto this blogspot for other reasons, but this was interesting. I certainly agree with the spirit of Crichton’s and lumo’s conclusions, especially the misuse of consensus as argument. However I think there are problems with the reasoning.

General:
1. The matter of the discussion spans from science to politics of science to politics in general. While science can be satisfied with ignorance of an answer (lumo: …”the physicists should have the freedom to pursue the ideas that they find likely and important,…”), in politics one has to decide what to do (or not) regardless. So the measure of success (or right) are different.

2. Some of the key terms are not well defined. ‘Consensus’ and ‘scientific consensus’ itself have several usages (http://en.wikipedia.org/wiki/Consensus, http://en.wikipedia.org/wiki/Scientific_consensus). Peer review is deemed non-consensus in the former but consensus in the latter, which lumo refers to.

Specifics:
lumo asserts Crichton’s reasoning: “His essays are very rational. They are based on purely scientific approach to the questions. He's able to deal with a lot of sources and references. This speech is no exception.” But there are many dubious points as has been discussed. I will add some more, specifics this time since otherwise this comment will be even lengthier.

3. Crichton criticizes some model equations (SETI, TTAPS):
If the equations are regarded as Bayesian statistics (the most useful theory of probability I know), an ansatz is not wrong however made, even a guess may suffice until experiments refine the probabilities or contradict the model.

Crichton says “The Drake equation cannot be tested and therefore SETI is not science.” This must be false since the terms can be tested and estimated; some will have to wait until ETI’s are observed, some may have to be clumped together.

4. Crichton on secondhand smoke:
He refers to a 1994 EPA pamphlet. I haven’t found it anywhere, but at http://www.tobacco-facts.info/second_hand_smoke.htm there is a reference to a 1992 EPA report that mentions the same “3,000 lung cancer deaths each year in nonsmoking adults”: EPA/600/6-90/006F December 1992
RESPIRATORY HEALTH EFFECTS OF PASSIVE SMOKING: LUNG CANCER AND OTHER DISORDERS.

Crichton: “In a 1994 pamphlet the EPA said that the eleven studies it based its decision on were not by themselves conclusive, and that they collectively assigned second-hand smoke a risk factor of 1.19. (For reference, a risk factor below 3.0 is too small for action by the EPA. Or for publication in the New England Journal of Medicine, for example.)”

The report uses meta-statistics, so while 3 of the 17 individual reports had a risk factor > 3.0, the combined risk factor of 1.81 was significant to p < 0.000001 for the null hypothesis. Obviously, many reports have < 3.0 risk factor and still gets published. Or keep only the 3 risky reports and you will still need to cut down on smoking.

Crichton: “Furthermore, since there was no statistical association at the 95% confidence limits, the EPA lowered the limit to 90%.”

The report repeatedly points out that they are using a one-sided interval which is why they report a 90 % confidence limit, but the null hypothesis still has p < 0.05.

5. Crichton on climate:
“Nobody believes a weather prediction twelve hours ahead. Now we're asked to believe a prediction that goes out 100 years into the future?”

Climate differ from weather, obviously. We can predict that a winter occurs somewhere every year with more than the usual probability in weather forecasts.

“But what are scientists doing attacking a press? Is this the new McCarthyism-coming from scientists? Worst of all was the behavior of the Scientific American,…”

Scientific American web-site looks like a thoroughly commercial press site, not part of the “scientific community” Crichton discusses.

To sum up the specifics, I can’t see much of the rationality or the ability to deal with references lumo asserts.

Actually both Crichton and I look like hacks on probability. He suggests that reports that has low risks should be excluded, and I fell for it... Of course all reports must be published and then used! So as luck would have it, yet another argument against Crichton.

The post Religious Science refers in part to the above post and comments. (This is a sort of manual trackback).

On second-hand smoke: The interesting stats are total mortality among smoker's spouses who have never smoked.

a recent study:

New Zealand researchers publish world's largest study on second-hand smoking and mortality

"Adults who have never smoked and who live with smokers have a 15% higher risk of death than those living in a smoke-free household," says Dr Sarah Hill, lead author of the Wellington School of Medicine and Health Sciences study published today by the prestigious British Medical Journal.

The research uses New Zealand Census-Mortality Study data for all adult census respondents who had never smoked and were aged 45-74 years at the time of either the 1981 or 1996 population censuses.

Smoking status data was available for all household members aged 15 and over, and death rates were monitored for three years after the two censuses.

Never smokers living in households with one or more current smokers were regarded as being exposed to secondhand smoke in the home. Those living in households with no current smokers were regarded as not exposed.

Adults who had never smoked and who lived with smokers had about a 15% higher risk of death than those living in a smoke-free household, even after taking into account differences in age, ethnicity, marital status, and socioeconomic position.

"Our finding is consistent with previous studies in this area, but is more precisely measured due to being based on a large study," says Dr Sarah Hill.

reader Luboš Motl said...

One should be kind of skeptical about the vague statements like "someone has a 15% higher risk of death". I thought that all of us had a 100% risk of death. ;-) They probably mean something like a death rate, but they don't exactly specify at which age the rate is measured etc.

Of course that the most natural way to measure such potential impact is the average lifetime.

On second-hand smoke:
capitalist is correct, there are several studies that conclude that smoking brings health problems. Which is contrary to Crichton's sweeping claims: "Meanwhile, ever-larger studies failed to confirm any association." And, as I pointed out, the pamphlet he refers to may not exist. But an earlier EPA study does, and he is wrong on EPA methods.

Crichton further makes the appalling suggestion that studies should be excluded from the data set (or publication) if they show a small (relative) risk: "a risk factor below 3.0 is too small for action by the EPA. Or for publication in the New England Journal of Medicine, for example." Disregarding the fact that such studies would help confirm his beliefs, it is WRONG, WRONG, WRONG, as lumo likes to say. All good studies must be published, of course.

On SETI:
Crichton says "The Drake equation cannot be tested and therefore SETI is not science." We know of intelligent life, so trying to gather more data is legitimate. The equation can be bayesian interpreted so is legitimate. It can also be tested, just not in the manner Crichton envisions. Furthermore it can then make predictions. (If we have data on a couple of ETI's, we can predict fL, the fraction of a planet's life during which the communicating civilizations live. And then we can sit back and observe, in theory at least. ;-)

On DDT:
lumo refers to more of Crichtons speeches in "Environmentalism as a Religion". Again, I agree with the spirit. (Not that environmentalism, whatever that is exactly, is a religion, but that it can be used as one.) But again there are large problems with the reasoning, fact and science.

lumo centers in on Crichtons discussion on DDT. This time lumo actually work through some of the arguments himself. But he misses Crichton's errors.

Crichton says: "I can tell you that DDT is not a carcinogen and did not cause birds to die and should never have been banned. I can tell you that the people who banned it knew that it wasn't carcinogenic and banned it anyway."

This is wrong since the ban wasn't based on that it should be a carcinogenic. In http://www.epa.gov/history/topics/ddt/01.htm we learn that "The cancellation decision culminated three years of intensive governmental inquiries into the uses of DDT. As a result of this examination, Ruckelshaus said he was convinced that the continued massive use of DDT posed unacceptable risks to the environment and potential harm to human health."

Furthermore the ban didn't much affect the use of DDT, it was going out anyway (except in poor countries): "The peak year for use in the United States was 1959 when nearly 80 million pounds were applied. From that high point, usage declined steadily to about 13 million pounds in 1971, most of it applied to cotton. The decline was attributed to a number of factors including increased insect resistance, development of more effective alternative pesticides, growing public and user concern over adverse environmental side effects--and governmental restriction on DDT use since 1969."

There is much more like this. Crichtons main ideas may be good but he doesn't do a good job on facts or science. And lumo maybe should have listened on what Crichton tried to tell him, that one must make his/hers own judgement on facts and references instead of going with a consensus or party lines.

Oh, and Crichton never mentions Rachel Carson in lumo's given reference. Is it just because she is a woman she is called "hysterical" here? Tsk, tsk!

My 2nd line should read "second-hand smoking" instead of "smoking". Sorry, it's late...

Lumo said -
One should be kind of skeptical about the vague statements like "someone has a 15% higher risk of death". I thought that all of us had a 100% risk of death. ;-) They probably mean something like a death rate, but they don't exactly specify at which age the rate is measured etc.
Since mortality means death rate, and they explicitly use the words "death rate," yeah - they "probably" do mean "something like a" death rate.

Lumo - Of course that the most natural way to measure such potential impact is the average lifetime.Not so. The lifetime impact is an average of the death rate over the number of years married to the smoker and other things. The mortality ("death rate") is a more fundamental statistic. Note that for the the much simpler case of radioactive decay, a 15% increase in "death" (decay) rate translates to a 13% shorter half-life. Because human decay rate increases dramatically with age, the impact is less, but a lifetime of being married to a smoker is still going to lop a few years off your life. Note also that this kind of statistic almost assuredly understates the risk due to second-hand smoke, since there are other sources of second-hand smoke that many or most are exposed to.

Even without these conclusive statistical studies, there are the known facts that cigarette smoke is carcinogenic and there don't seem to be "safe" levels for mutagens.

reader Luboš Motl said...

Well, if they say what I say, then it's probably OK. ;-) Your previous posting said nothing about the death rate. It cited Sarah Hill who talked about the risk of death.

It's very questionable in estimating these probabilities whether you should count the life with a smoker as an accumulative effect that lasts even after you divorce, or whether you just increase the rate temporarily etc.

I would be very surprised if the statements with 15% were true because a permanent life with a smoker would then reduce life by 15% - I think that this is not even what first-hand smoking does. There are other papers that seem to directly contradict yours, so I don't know. I would have to study these things in detail.

To quote from my first secondhand smoke post: "and death rates were monitored for three years after the two censuses"

Sounds like they mentioned death rate to me.

I don't think I should need explain elementary statistics to a Harvard physics prof, but you make a number of statements that show you don't understand the methodology. The study is controlled for age, sex, race and socioeconomic status. For each subgroup, the number of deaths during the study period is compared to the number in the subgroup, and divided by the time period to get a death rate. The death rate of each subgroup among the not married to smokers is compared to the corresponding subgroup among the married to smokers. This gives a death rate difference for each cohort. I expect the 15% number was computed by computing the group-size weighted average of the death rate differences.

The New Zealand study is consistent with many others. I only looked at one Crichton study, and it had the obvious flaw of only considering a couple of specific causes of death, and hence had poor statistics as well as failing to deal with other potential causes of the excess mortality.

Crichton is not a trustworthy source. He makes stuff up for a living - literally and literarily. It's what made him rich and famous.