Book Club: Wrong, Chapter 2:
|…[F]ilmmaker Kenneth Bowser…does an admirable job of conveying why Ochsí music continues to mean so much to his fans. … Bowser has unearthed who knows how many hours of unseen footage…. These alone make the film a must-see for fans like me.|
|Source: Ad for Phil Ochs: There but for Fortune, The New York Times, 1/28/2011, p. C18||Source: Simon Vozick-Levinson, "'Phil Ochs: There but for Fortune,' a great documentary about an underappreciated folk singer", Entertainment Weekly, 12/10/2010|
So, it's a must-see for fans of Phil Ochs like Vozick-Levinson, which is kind of an important qualification.
A new slogan seems to be popular: "If guns kill people, then pencils misspell words." This is obviously a variant of the old slogan: "Guns don't kill people. People kill people." My favorite variant is the Chuck Norris one I've used as a title for this post.
The new slogan differs from the old in being a conditional statement; more specifically, a conditional statement similar to the familiar "monkey's uncle" type. For instance: "If guns kill people, then I'm a monkey's uncle", or "if guns kill people, then I'm Marie of Romania." Such a statement is a rhetorical way of negating its antecedent: Since pencils don't misspell words, then guns don't kill people, by Modus Tollens. Thus, the new slogan is equivalent to the first part of the old one.
Of course, guns do kill people, as do bullets, knives, cars, trains, falling trees, meteorites, and many other inanimate objects. So, what is meant by denying that they do?
According to my dictionary, the word "kill" is ambiguous between a meaning that can apply to inanimate objects such as guns, and a meaning synonymous with "commit murder". I'm doubtful of my dictionary, that is, I wonder whether it's true that "kill" is ambiguous between a broad meaning that includes inanimate objects and a narrower one restricted to people, since the single broad meaning covers both cases. However, such an ambiguity would explain the meaning of the slogan, that is, the slogan denies that guns kill people in the narrower sense of "kill". Clearly, guns cannot commit murder, just as pencils cannot misspell words.
However, why make a point of the obvious fact that guns don't commit murder? My sense is that the slogans are meant to advocate a policy of punishing people for committing crimes as opposed to attempting to prevent crime by restricting access to guns. Since a slogan is not an argument it is, a fortiori, not a fallacious argument. Therefore, it cannot, strictly speaking, commit a logical fallacy. However, I think these slogans are logical boobytraps for at least two fallacies:
Acknowledgment: Thanks to Woody NaDobhar for raising the issue.
Sleights of Mind, subtitled "What the Neuroscience of Magic Reveals about our Everyday Deceptions", is a new book by the neurologists Stephen Macknik and Susana Martinez-Conde―together with the science writer Sandra Blakeslee. I've said before that psychologists could learn a lot from magicians, so it's nice to see two doing so.
I haven't read the whole book yet, only parts of it, but looked through the rest. While most of it has little bearing on logical fallacies or related matters, the later chapters get into cognitive illusions. For instance, the first few chapters deal with attention, and how magicians use misdirection to keep people from seeing how a trick works―which is a more powerful effect than most people realize. Visual illusions are another early topic. Later chapters, however, discuss "illusory correlations", which are false causal conclusions, as well as the gambler's fallacy and some other probabilistic errors.
John Allen Paulos' latest "Who's Counting" column deals with the same subject as our current book club, namely, why scientific studies so often turn out wrong. By the way, I hope to have the next, belated installment of the club later this month.
I agree with Paulos that we shouldn't be so surprised when a study is contradicted by a later one. According to Paulos, one reason why this happens is regression to the mean. Read the whole thing.
Source: John Allen Paulos, "Study vs. Study: The Decline Effect and Why Scientific 'Truth' So Often Turns Out Wrong", Who's Counting, 1/2/2011
Update (1/8/2010): Also check out the article by Jonah Lehrer from The New Yorker that seems to have prompted Paulos' column. Unlike Freedman in Wrong, who writes as if one study on its own should be enough to establish a result, Lehrer appreciates the importance of replication:
Before the effectiveness of a drug can be confirmed, it must be tested and tested again. Different scientists in different labs need to repeat the protocols and publish their results. The test of replicability, as itís known, is the foundation of modern research. Replicability is how the community enforces itself. Itís a safeguard for the creep of subjectivity. Most of the time, scientists know what results they want, and that can influence the results they get. The premise of replicability is that the scientific community can correct for these flaws.
However, Lehrer has his own problem:
For many scientists, the [decline] effect is especially troubling because of what it exposes about the scientific process. If replication is what separates the rigor of science from the squishiness of pseudoscience, where do we put all these rigorously validated findings that can no longer be proved? Which results should we believe?
Strictly speaking, theorems in logic and math are "proven", but empirical science never "proves" anything, except in a weak, everyday sense of the word. If we expect a medical study, even one that's been successfully replicated, to "prove" the effectiveness of a drug, then we're going to be shocked and disappointed when later studies show the drug to be less effective. 5% of studies may show a statistically significant effect just by chance! That's not even considering all the nonrandom ways that a study may go wrong.
Lehrer writes: "The decline effect is troubling because it reminds us how difficult it is to prove anything." Difficult? Impossible is more like it, unless you're talking about math. At the end of the article, Lehrer goes off the deep end into skepticism, but that isn't warranted by the "decline effect". Yes, science is hard: get used to it!
While regression to the mean may play a role in some of these cases of the "decline effect"―as Paulos suggests, and as is mentioned in Lehrer's article―I think that the simplest explanation in many cases is that the effect being studied is unreal. For example, in the case of ESP, the most likely explanation for Rhine's failures to replicate his early experiments is that he tightened up his controls for the later ones, thus eliminating the supposed effect. It doesn't bode well for the status of the "decline effect" as some kind of real phenomenon that Rhine is considered a prominent example.
Source: Jonah Lehrer, "The Truth Wears Off", The New Yorker, 12/13/2010
The Agency for Counter-Terrorism (ACT) has received information that a European terrorist known as "the Hyena" has entered the United States under an assumed name. Unfortunately, ACT has also received conflicting reports of the Hyena's alias, making it hard to track him down, especially since each of the names is a common one. Four informants were questioned and gave the following information about the alias:
According to the ACT, the fourth informant is the most reliable. Assuming that the fourth informant is correct, what is the Hyena's alias?
Solution to the Puzzle of the Hyena's Alias: The Hyena's alias is "James Wilson". There are several ways to solve this puzzle, but perhaps the simplest is to realize that, if the fourth informant is correct, then the Hyena's alias must be either "John Moore" or "James Wilson". This is because each of the first two informants must be right about one of the names but not both, therefore one must be right about the first name and the other right about the surname. Then, the third informant's information allows us to eliminate "John Moore": since we've already ruled out "Taylor" as the last name of the alias, the third informant must be right that the first name is not "John".
Source: J. A. H. Hunter & Joseph S. Madachy, Mathematical Diversions (1975). The puzzle is based on one from page 49.