Eight Preposterous Propositions: From the Genetics of Homosexuality to the Benefits of Global Warming

by Robert Ehrlich

Book Overview

Placebo cures. Global warming. Extraterrestrial life. Psychokinesis. In a time when scientific claims can sound as strange as science fiction--and can have a profound effect on individual life or public policy--assessing the merits of a far-out, supposedly scientific idea can be as difficult as it is urgent. Into the breach between helpless gullibility and unyielding skepticism steps physicist Robert Ehrlich, with an indispensable guide to making...

• Format: Hardcover
• Language: English
• ISBN: 0691099995
• ISBN13: 9780691099996
• Release Date: October 2003
• Publisher: Princeton University Press
• Length: 360 Pages
• Weight: 1.20 lbs.
• Dimensions: 1.1" x 5.5" x 8.5"

Customer Reviews

Not as preposterous as you might think

Physicist Robert Ehrlich returns with another survey of interesting but unproven ideas, and "8 Preposterous Propositions" is considerably more daring, politically, than his first venture, "9 Crazy Ideas in Science." The eight ideas, all posed as questions, are: Is homosexuality primarily innate, is intelligent design a scientific alternative to evolution, are people getting smarter, can we influence matter by thought alone, should we worry about global warming, is complex life in the universe very rare, can a sugar pill cure us and should we worry about cholesterol? After reviewing the evidence, Ehrlich finds only one of the eight to be complete moonshine -- four flakes in his rating system. Two of the other seven he finds not flaky at all (zero flakes), and the rest somewhere in between. "This is not a debunking book," writes Ehrlich. Nor does he seem to have chosen his subjects with any agenda in mind. Every one of the eight is something that shows up from time to time in the letters to the editor, but his selection is impartial as between left/right or conservative/liberal politics. "It sometimes seems that nothing is too strange to be true," he writes. On the other hand, just because something is strange does not make it valid. The problem is, with so many unsettled ideas out there, how does a person form a solid opinion about all of them -- or should he? The late sociologist Aaron Wildavsky proposed that almost all public issues, no matter how complex they seemed, were within the understanding of an ordinary careful citizen. Of course, his definition of ordinary citizen was a Berkeley grad student with a year to spend investigating one question. Ehrlich is neither so certain nor so hardnosed as Wildavsky, but he still sets a pretty high standard. "If the uncertainties are simply a matter of our laziness in not looking into an issue deeply enough, then relying on our instincts is very unfortunate." True, but who has time to track down and read a hundred reports, as Ehrlich did in investigating cholesterol, which is the most curious and most interesting of his eight latest questions. That chapter includes lengthy discussions of statistical analysis of medical experiments and why and whether "negative" results of experiments should be published (few are). These ideas apply to most medical decisions, not just whether to take cholesterol lowering drugs or eat that hamburger. Ehrlich's books are not really about what we know, but how we know we know it. Some psychologists have contended that only a few people (one in eight, they suggest) are capable of questioning their own beliefs, even when asked to do so. Ehrlich is in the minority. While reading up on cholesterol, "I ended up changing my mind at least three times," he writes. Postscript: This review was written when the book was published in 2003. At the time, I chose not to say anything about global warming, but time passes, and the particular way Ehrlich phrased his question -- should we wo

Scientific Thinking Can Be Fun

8 Preposterous Propositions by Robert Ehrlich, the sequel to Nine Crazy Ideas In Science, takes on eight newsworthy issues in science and evaluates them for their flakiness factor. As with the original book, Ehrlich lays out the evidence evenhandedly for each issue and then at the end of each chapter assigns each issue 0 to 5 flakes. Like the first book, 8 Preposterous Propositions is an excellent exercise in scientific thinking and would be a good way to lure a nonscientist towards the joys of scientific thinking. I look forward to 7 Scintillating Suggestions or 10 Titillating and Tenuous Thoughts or whatever the next book will be called.

Analyzing some timely issues

Robert Ehrlich tackles eight interesting and often timely topics including the possibility of homosexuality being genetic and the possible "benefits" of global warming. The book does an excellent job of giving each proposition the benefit of the doubt and carefully examines the evidence for and against. In the chapter "Can Sugar Pills Cure You?" Ehrlich not only addresses the proposition that placebo's actually work in helping with pain (not a surprise) but also discusses how easy it is for a drug that is essentially a placebo to get FDA approval. The FDA doesn't require double blind tests to use "active" placebo's i.e. placebo's that mimic a drugs side effect. This can easily cause the test to become unblinded. Since a drug only needs to be a small fraction more effective than the placebo, unblinding can easily give a false positive. This is only one way in which FDA approval is flawed. A drug like Prozac shows little effectiveness beyond the placebo effect yet has a 225,000 percent markup over manufacturers cost. The chapter on Global Warming presented a lot of information for and against the dangers of Global Warming. The end result seemed to be that Global Warming is more than likely occuring but he gave one flake for the proposition that we shouldn't worry about it. Based on the information in the chapter the flakiness of not worrying about Global Warming would seem to be specific to the individual. A teenager should probably be more worried than a seventy year old. Someone living on the coast should be more worried than someone living inland and someone living in a third world country should be more worried than someone living in the United States. It seems odd that Ehrlich gave a universal one flake. The final subject on high cholesterol being perfectly safe played off like a tennis match. Does high cholesterol increase the risk of congenital heart failure or not? The evidence seemed to go back and forth but in the end Ehrlich sided with the evidence that lowering your cholesterol is healthy for your heart. However he does once again take a deserved swipe at the FDA with respect to some cholesterol reducing drugs such as gemfrobrizil, lovastatin and clofibrate. Many healthy people are being encouraged to take these statins and Ehrlich has concerns that the people taking these drugs are essentially guinea pigs similar to the women who had hormone replacement therapy and discovered that the cure was worse than the disease. These drugs may be carcinogenic and raise the risk of cancer. Although the book is about specific topics it's a great guide for learning scientific analysis in general. Understanding terms like "regression to the mean" can actually be applied to real world problems. I highly recommend this book to anyone who wants to increase their analysis and decision making abilities.

A mixed bag.

This book does a fairly lucid and impartial job of examining eight potentially controversial claims.The best chapter is the one on placebos, which convinced me that my previous reasons for believing in a placebo effect were wrong, and then showed that it was still quite possible that placebo effects are real.But much of the book is a good deal more forgettable. His discussion of homosexuality might strike a few rabid Lysenkoists as preposterous, but most educated people should find his answers unsurprising. And his approach isn't nearly as valuable when dealing with hotly debated topics such as global warming as it is when he is bringing overlooked controversies to our attention.