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Layzej writes: Prominent scientists, science communicators, and skeptic activists, are calling on the news media to stop using the word "skeptic" when referring to those who refuse to accept the reality of climate change, and instead refer to them by what they really are: science deniers. "Not all individuals who call themselves climate change skeptics are deniers. But virtually all deniers have falsely branded themselves as skeptics. By perpetrating this misnomer, journalists have granted undeserved credibility to those who reject science and scientific inquiry."

Layzej writes: Prominent scientists, science communicators, and skeptic activists, are calling on the news media to stop using the word "skeptic" when referring to those who refuse to accept the reality of climate change, and instead refer to them by what they really are: science deniers. "Not all individuals who call themselves climate change skeptics are deniers. But virtually all deniers have falsely branded themselves as skeptics. By perpetrating this misnomer, journalists have granted undeserved credibility to those who reject science and scientific inquiry."

anagama writes "For anyone who cringes whenever accosted by topics such as psychics, haunted houses, or any sort of new age drivel; for anyone who thinks James Randi is cool or has an active subscription to the Skeptical Inquirer - you're gonna love this story about infrasound. Here's a quote: "British scientists have shown in a controlled experiment that the extreme bass sound known as infrasound produces a range of bizarre effects in people including anxiety, extreme sorrow and chills -- supporting popular suggestions of a link between infrasound and strange sensations. ... Some scientists have suggested that this level of sound may be present at some allegedly haunted sites and so cause people to have odd sensations that they attribute to a ghost -- our findings support these ideas.""

Max Tardiveau writes "I just finished Nassim Nicholas Taleb's Fooled by Randomness. It is an enjoyable book, written engagingly by an interesting character -- the kind of book that makes you think twice about certain things (for instance, the fact that you're not dead: is that really because you're so darn good, or does dumb luck play a part?) Although written all the way back in 2001, this book is more relevant than ever, since one of its major topics is the impact of unpredictable events on markets, insurance, and our perception of life in general. In fact, Taleb makes a living from unforeseen events; these days, that seems like a rather cunning niche." Read on for the rest of his review of this book. Fooled by Randomness author Nassim Nicholas Taleb pages 220 publisher Texere rating 8 reviewer Max Tardiveau ISBN 1587990717 summary Debunking fallacies of observation, Taleb reminds us of the pervasive ineffables that complicate life at every turn.

The main topic of the book is the fact that all humans are simply terrible at judging probabilities. Taleb is a securities trader, so a lot of the book revolves around financial probabilities, but his argument is mainstream and requires absolutely no knowledge of the markets. The book details examples of people wildly misjudging risks and probabilities in many contexts. Often that misestimation is understandable in advance of certain events, but harder to excuse after they've occurred; Taleb hits pretty hard on what he calls "data snoopers," his term for people who back-fit theories to existing data.

One of the most notorious examples is the Bible code (which has been thoroughly debunked), but Taleb argues that analysts who spend their time trying to find patterns in historical market data are no different: if you try long enough and hard enough, you will unavoidably find apparent regularities, which can be extremely compelling when seen in isolation. In context, though, they dissolve into nothing but meaningless statistical anomalies. Taleb rightfully compares these searches for meaning to the famous monkeys and typewriters parable.

Taleb's best example of poor probability intuition is probably the infamous survivor bias, which is our tendency to be disproportionately impressed by success. We almost always ignore the fact that, for one success story, there are many failures. But we seldom hear about the failures (just like we never hear about the many theories that didn't fit the data). So it's all a game of numbers: out of 10,000 traders, a few are statistically bound to be successful, even if they are nothing more than lucky idiots. The fact that they succeeded does not mean anything. It doesn't mean that they are bad traders, but it doesn't mean that they are good traders either, because on average somebody had to succeed.

One of Taleb's hot buttons is that people tend to be too confident in what they know. He argues convincingly that we should take everything, including science, with a grain of salt. Writing about Karl Popper, he points out that there are only two kinds of scientific theories: those that are demonstrably false, and those that are not yet demonstrably false. An irksome (but sadly true) observation, yet most people behave as if what they know is eternal truth. One could of course argue that Popper's observation is but another kind of truth, but I tend to put a lot more trust in people who question what they know than in people who don't.

Another of Taleb's peeves is the human tendency to over-attribute every random event (the old post hoc, ergo propter hoc). For instance, a commentator saying that "the Dow went down ten points today on concerns about Iraq" is talking nonsense: there is no way anyone can tie such a small market move to any particular reason. I found this specific point (which in retrospect is blindingly obvious) especially enlightening, as I am embarrassed to admit that, until now, I just accepted those market comments at face value.

Taleb also has some fun at the expense of economists and analysts, especially those whose predictions turned out wrong, but who claim that the theories were in fact right, and that the facts simply weren't supposed to be that way. This is what he calls denial of history, and is common among investors and gamblers (the two being of course close cousins).

The style of the book is informal and funny, and often meandering. We hop from one topic to the next, which occasionally may detract from the book's continuity, but overall the author's points come through loud and clear. Ironically for a man who advocates self-doubt, Taleb is starkly self-confident, though not in an irritating way.

Taleb is an intriguing, multi-cultural, iconoclastic character that has been around Wall Street for a while, and now runs his own small firm. Malcolm Gladwell (author of The Tipping Point, an absolute must-read for anyone who owns a brain) has written an excellent article that shows how Taleb's reasoning runs counter to just about every bit of conventional Wall Street wisdom. If you're interested in the markets, especially derivatives, and how Taleb trounces most of Wall Street's voodoo doctors, this moderately technical interview from 1996 is worth reading too.

Overall, a warmly recommended book.

You can purchase Fooled by Randomness from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

Tal Cohen writes: "It is said that one of the most important skills a physicist needs is the ability to quickly make "back-of-the-envelope" calculations. For example, Jan Wolitzky (in Jon Bently's "Programming Pearls") tells about Enrico Fermi, Robert Oppenheimer, and the other Manhattan Project brass who were behind a low blast wall awaiting the detonation of the first nuclear device from a few thousand yards away. Fermi was tearing up sheets of paper into little pieces, which he tossed into the air when he saw the flash. After the shock wave passed, he paced off the distance traveled by the paper shreds, performed a quick "back-of-the-envelope" calculation, and arrived at a figure for the explosive yield of the bomb, which was confirmed much later by expensive monitoring equipment." Read on to find out what this has to do with the unusual characteristics of Earth, and how they could influence our search for life elsewhere in the universe. Rare Earth: Why Complex Life is Uncommon in the Universe author Peter D. Ward, Donald Brownlee pages 368 publisher Copernicus rating 7 reviewer Tal Cohen ISBN 0387987010 summary Maybe we are alone, after all.

But expensive monitoring equipment which can confirm the calculation does not always exist, and hence in some fields, our entire knowledge is based on back-of-the-envelope calculations and rough estimates.

Take, for example, the following question: "How many intelligent civilizations, capable of radio communications, currently exist in the Milky Way galaxy?". The worthwhileness of search projects (such as SETI) is closely related to the answer to this question. The number of positively known civilizations is exactly one: the human civilization. And yet, many scientists believe, or at least believed until recently, that the actual number is far, far higher.

This belief was based on various estimates, such as the calculation proposed by Frank Drake, now known as "The Drake Equation." This equation was popularized in Carl Sagan's remarkable TV series, "Cosmos". Sagan himself believed the calculation's result, and was one of the founders of SETI.

Drake's equation is easy to understand. Take the number of stars in the galaxy (about 200 to 300 billion, based on generally accepted estimates), and multiply it by: the percentage of stars that are similar to our Sun in the energy output and stability; the percentage of stars that have planets (since not every star has any); the percentage of planets orbiting their star in a proper distance (so they could hold liquid water, a necessity for maintaining life); the percentage of planets with liquid water on which life actually evolved; and finally, the percentage of life-bearing planets in which intelligent civilizations (i.e., those that can communicate by radio) eventually came to be. All in all, there are five or six factors in this product.

(Note: In my own copy of the book (2nd impression), page 267 states that "a good estimate for the number of stars in our galaxy [is] between 200 and 300 million" - one letter misspelled, and wrong by three orders of magnitude. I do hope the authors' actual calculations were based on the correct value.)

But what values should be used for the various percentages? Drake (and Sagan) chose what they considered to be a conservative approach, and estimated that only about 1 in 10 stars has any planets; only 1 in 10 planets is in the proper orbit, and so forth. Despite the conservative approach, the results were encouraging, indicating that there are thousands of intelligent civilizations in the Milky Way, and probably millions of them in the whole universe. Thus they concluded that there is intelligent life out there, in all likelihood; now we only have to look for it.

In their book Rare Earth, published by Copernicus Press in 2000, Peter Ward and Donald Brownlee point at Drake's (and other physicists') mistakes in a long and depressing discussion, a discussion that took the wind out of more than one SF author's sail.

The book presents what the authors call "the rare Earth hypothesis": simple (bacterial) life is very common in the universe; complex life (multi-cellular life forms, or animals -- let alone intelligent life) is very rare. The first part of the hypothesis is easy to understand, and few scientists will argue with it: indications of simple life were already discovered on rocks originating on Mars, and even here on Earth in conditions that were, until recently, considered completely hostile to life (such as temperatures higher than 100 degrees Celsius, in which 'extremophile' bacteria were found to exist). The second part is the interesting one, and it suggests that the existence of simple life does not necessarily lead to the evolutionary development of complex life, for any number of reasons.

Drake's mistake was basically in the assumption that all it takes for a planet to develop life is being in the proper distance from a proper star. The truth, Ward and Brownlee suggest, is that we have to look at each and every attribute of Earth, and re-estimate its importance for supporting life. Drake's equation is a statistical calculation, but with no other example for life, we're doing statistics with N=1.

Well then, what are the special attributes of Earth that we have to take into account when attempting to run this calculation?

• Proper distance from the star. If a planet orbits its sun too closely or too far away, liquid water would not exist. There isn't much margin for error here: a change of 5 to 15 percent in Earth's distance from the Sun would lead to the freezing, or boiling, of all water on Earth.
• Proper distance from the center of the galaxy. The density of stars near the center of the galaxy is so high, that the amount of cosmic radiation in that area would prevent the development of life.
• A star of a proper mass. A too-massive star would emit too much ultra-violet energy, preventing the development of life. A star that is too small would require the planet to be closer to it (in order to maintain liquid water). But such a close distance would result in tidal locking (where one face of the planet constantly faces the star, and the other always remains dark -- as with the moon in its orbit around Earth). In this case one side becomes too hot, the other too cold, and the planet's atmosphere escapes.
• A proper mass. A planet that is too small will not be able to maintain any atmosphere. A planet that is too massive would attract a larger number of asteroids, increasing the chances of life-destroying cataclysms.
• Oceans. The ability to maintain liquid water does not automatically imply that there will be any on the planet's surface. It looks like Earth acquired its own water from asteroids made of ice that crashed here billions of years ago. On the other hand, too much water (i.e., a planet with little or no land) will lead to an unstable atmosphere, unfit for maintaining life.
• A constant energy output from the star. If the star's energy output suddenly decreases, even for a relatively short while, all the water on the planet would freeze. This situation is irreversible, since when the star resumes its normal energy output, the planet's now-white surface will reflect most of this energy, and the ice will never melt. Conversely, if the stars energy output increases for a short while, all the oceans will evaporate and the result would be an irreversible greenhouse-effect, preventing the oceans from reforming.
• Successful evolution. Even if all of these conditions hold, and simple life evolves (which probably happens even if some of these conditions aren't met), this still does not imply that the result is animal (multi-cellular) life. The evolution of life on Earth included some surprising leaps; two worth mentioning are the move from simple, single-cellular life to cells which contain internal organs, and the appearance of calcium-based skeletons. It appears like the first of these leaps took more time than the evolution from complex single-celled life to full-blown humans.
• Avoiding disasters. Any number of disasters can lead to the complete extinction of all life on a planet. This include the supernova of a nearby star; a massive asteroid impact (like the one that probably caused the extinction of dinosaurs, and 70% of all other life-forms at the time); drastic changes of climate; and so on.

There are also a few attributes that seem, at first, to be completely unrelated to life and not required for its development. Ward and Brownlee argue strongly for the importance of the following attributes:

• The existence of a Jupiter-like planet in the system. Apparently, Jupiter's large mass attracted many of the asteroids that would have otherwise hit Earth. Could life evolve in a system with no Jovian planet? On the other hand, too many Jovian planets, or one that is too large, could lead to a non-stable solar system, sending the smaller planets into the central sun or ejecting them into the cold of space.
• The existence of a large, nearby moon. Luna, Earth's moon, is atypically large and close. Both of Mars's moons, for example, are minor rocks by comparison. What does this have to do with life? Well, it turns out that Luna kept (and still keeps) Earth's tilt stable. Without Luna, the tilt would have changed drastically over time, and no stable climate could exist. If the tilt would have stabilized on a too-large or too-small value, the results could also be disastrous; Earth's tilt is "just right."
• Plate tectonics. Surprisingly enough, it seems like plate tectonics are required for maintaining a stable atmosphere. Plate tectonics play an important role in a complex feedback system (explained in detail in the book) that prevents too many greenhouse gases from existing in the atmosphere. No other planet (except maybe for Jupiter's moon Europa) is known to have plate tectonics. Is this a rare phenomenon, but required for life?

The bottom line is that many additional factors must be added to Drake's equation. One must keep in mind that as any term in such an equation approaches zero, so too does the final product. For most terms, we have no way of reliably estimating their true value, but it seems like at least some of these values are extremely low.

Two important things should be noted about this book. First, about what it does not contain: although I am sure many people will see the Rare Earth Hypothesis as another proof for the existence of a god, this notion of a proof is completely unrelated to the authors' ideas. The hypothesis claims that the conditions for creating complex life are rare; but we know for a fact that at least in one case, all the required conditions were met. Additionally, anyone who insists on taking the ideas of this book as a proof for god's existence will also have to accept the authors' prepositions about the age of the universe, the age of planet Earth, and more importantly, the theory of evolution.

Second, about what the book does contain: the book discusses at length all the issues I've listed above, and more. The problem is that sometimes one gets the feeling that these issues are discussed in too much detail, and the authors tend to repeat themselves, or to delve too deep into some of the less-important aspects of their theory. This is certainly not your common popular-science book; it relies on very up-to-date research results (including some results that were not even published when the book went to press). The writing gets technical on many points in astrophysics, biology, chemistry, and geology (as well as the new field of astrobiology, of course). Over 25 pages of bibliography and references are included.

The theory's weakest point, however, is obvious. The authors admit (after 281 pages of discussion) that their base assumption was that every complex life-form would be similar in many ways to life on Earth: "We assume in this book that animal life will be somehow Earth-like. We take the perhaps jingoistic stance that Earth-life is every-life, that lessons from Earth are not only guides but also rules. We assume that DNA is the only way, rather than only one way" (p. 282).

For me, reading this book was a fascinating and awe-inspiring experience. The most important conclusion (apart from SETI being a huge waste of resources) is an unavoidable cliché, which the authors avoided presenting directly, even though it stares into the reader's face from every page and each paragraph: What we have here is rare, maybe even unique. We should try a little harder to make sure it survives.

Post Scriptum: A news item in the November/December 2001 issue of the Skeptical Inquirer (Vol. 25, No. 6) states that "David Darling, an astronomer who is a critic of the Rare Earth hypothesis, has revealed that one of the strongest influences on the authors, a young [...] astronomer who they acknowledge in their preface 'changed many of our views about planets and habitable zones', has a hidden, Earth-is-unique agenda motivated by strong 'intelligent design' religious views." That astronomer, Guillermo Gonzalez, published several articles in Connections, a quarterly newsletter published by Reasons to Believe, Inc. In one of these articles, co-authored with the creationist scientist Hugh Ross, Gonzalez writes: "The fact that the Sun's location is fine-tuned to permit the possibility of life [...] powerfully suggests divine design."

Darling published these findings, along with a detailed point-by-point scientific critique of the Rare Earth hypothesis, in his book Life Everywhere: The Maverick Science of Astrobiology . Skeptical Inquirer quotes Darling as saying, "What matters is not whether there's anything unusual about the Earth; there's going to be something idiosyncratic about every planet in space. What matters is whether any of Earth's circumstances are not only unusual but also essential for complex life. So far we've seen nothing to suggest there is."

For more about this book, please see this page. For additional book reviews, please visit Tal's bookshelf. You can purchase Rare Earth from bn.com. Want to see your own review here? Just read the book review guidelines, then use Slashdot's handy submission form.

Patrick Fitzgerald writes: "The Supreme Court agreed Tuesday to intervene in a fight over copyrights, deciding whether Congress has sided too heavily with writers and other inventors. The outcome will determine when hundreds of thousands of books, songs and movies will be freely available on the Internet or in digital libraries." Openlaw's Eldred v. Ashcroft page has more information about the case, which seeks to challenge the most recent retroactive extension of copyright terms.