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March 5th, 2010 (Permalink)

Intensional Fallacy

"Intensional fallacy" is the name of a new fallacy, or perhaps a new name for an old fallacy. I came across the fallacy under this name for the first time in a long, fascinating book review by philosophers Ned Block and Philip Kitcher. I'll let them introduce the book and its authors:

In their controversial new book, What Darwin Got Wrong, Jerry Fodor and Massimo Piattelli-Palmarini set out to dismantle [the Darwinian] framework. They argue that standard evolutionary thinking―what they call Darwinism―is guilty of a basic logical error, not a mistake in biology but an "intensional fallacy." That fallacy, they say, undermines the entire enterprise.

I've never heard the term "intensional fallacy" before. That fount of all human wisdom, Wikipedia, has an entry for it, but the description is of the Masked Man Fallacy. More importantly, the Internet Encyclopedia of Philosophy has a brief entry in its article on fallacies, but it also describes the Masked Man Fallacy.

"Intensional fallacy" is an unfortunate name as it is pronounced and spelled almost exactly the same as the more familiar "intentional fallacy". The intentional―with a "t"―fallacy is not a logical fallacy, but is the supposed mistake of judging a work of art based on the intentions of the artist. Here's Block and Kitcher's description of the intensional―with an "s"―fallacy:

[Fodor and Piattelli-Palmarini] allege that Darwinism is guilty of an "intensional fallacy." … There are some sentences in which, if you substitute one name for another, and both are names for the same thing or person, you always go from a true sentence to a true sentence, or from a false sentence to a false sentence. "Madonna" and "Louise Ciccone" name the same person. The sentence "Madonna is a woman" is true. If you substitute "Louise Ciccone" for "Madonna," you obtain the sentence "Louise Ciccone is a woman," which is also true. Not all sentences work this way. Our world is full of people who do not know that Madonna is Louise Ciccone. If Bert is one of these people, then the sentence "Bert believes that Madonna is a star" may well be true, even though "Bert believes that Louise Ciccone is a star" is false. … There are some contexts, such as "is a woman," in which substitution of names that name the same entity preserves truth (or falsehood); these contexts are said to be extensional. Other contexts, such as "Bert thinks that is a star," allow for changes from truth to falsehood under similar substitutions; these are intensional.

This sounds like the beginning of a description of the Masked Man Fallacy, but never quite says what the fallacy is. In the Masked Man, one makes the mistake of substituting identicals into an intensional context, as if it were an extensional one. Using Block and Kitcher's example, to conclude that Bert believes that Louise Ciccone is a star from the fact that he believes Madonna is a star would be to commit the Masked Man Fallacy―or masked woman, in this case.

I'm not sure from the review what Fodor/Piattelli-Palmarini/Block/Kitcher mean by "intensional fallacy". It appears not to be the same as the Masked Man Fallacy, though clearly related. It may be either a more general fallacy, or perhaps the sibling fallacy of substituting co-extensional predicates within an intensional context. Perhaps the book is clearer.

I expect that I'll have more to say about the review soon, so read the whole thing and come back later. Be warned that it's a fairly philosophically sophisticated review, though not technical in terms of logic, and there's some mildly sophisticated discussion of evolution.

Sources:

Update (3/7/2010): In reading the following, keep in mind that I haven't read the book yet, and so am relying upon the accuracy of Block and Kitcher (B&K)'s description of its contents.

The notion of "intension", and the related one of "extension", that seems most relevant here applies to properties such as "having a heart". The extension of "having a heart" is simply the class of everything that has a heart, whereas its intension is closer to what we think of as its meaning, namely, "having an organ that pumps blood" or whatever. Two properties that have different intensions may have the same extension, in which case they are called "co-extensive". For instance, "having a heart" and "having a kidney" are co-extensive.

Given that, I still can't figure out what the "intensional fallacy" is supposed to be. According to B&K, the problem is that evolution cannot make fine-grained intensional distinctions between properties, but only coarse extensional ones. That is, assuming that you have two intensionally different but co-extensive properties, there's no fact of the matter as to which one evolution selects for or against.

Natural selection and selective breeding differ in that the former can only differentiate extensionally distinct traits, whereas the latter can differentiate between intensionally distinct but co-extensive traits. For instance, a breeder of moths might select for a trait such as black wings, but it could be that black wings are co-extensive with nocturnal inactivity. Nonetheless, we can still say which trait is selected for, because the breeder can tell us. In contrast, we can't ask nature which it was selecting, so there is no fact of the matter whether evolution selected for black wings or nocturnal inactivity.

Where's the fallacy here? I don't even see the argument that's supposedly fallacious, which makes me wonder whether F&P are using the term "fallacy" in some unusual sense.

Keeping in mind that I'm no expert on evolution―and I haven't even read the book!―this strikes me as an interesting logical fact about natural selection, but one that doesn't undermine "Darwinism". In most cases where there are two intensionally-distinct but co-extensive traits―such as black wings and nocturnal inactivity―there are probably ways of telling which is selected for. For instance, we can take some nocturnally-active moths that have light-colored wings, paint their wings black, and see whether they are as successful at reproducing as the black-winged nocturnally-inactive moths. In other words, we would make the traits no longer co-extensive and see what happens.

In contrast, if two traits are linked in a way that cannot be causally teased apart, then it seems incorrect to say that evolution selected for one but not the other: it's either both or neither. But so what? I don't see how that undermines natural selection. It might undermine some hastily-drawn conclusions about what traits are naturally selected, but it wouldn't undermine the fact that some set of traits is, in fact, selected. It may complicate the story, but not show that it's fiction.

I may have more to say about this review in the future, but I'm afraid that I'm going to have to read the book itself if I want to get a better handle on the elusive "intensional fallacy".

March 2nd, 2010 (Permalink)

Untie the Nots, Part 4

In his famous essay, "Politics and the English Language", George Orwell gives what he calls "four specimens of the English language as it is now habitually written" as illustrations of "the mental vices from which we now suffer". The following sentence, by Harold Laski, is the first of these four:

I am not, indeed, sure whether it is not true to say that the Milton who once seemed not unlike a seventeenth-century Shelley had not become, out of an experience ever more bitter in each year, more alien to the founder of that Jesuit sect which nothing could induce him to tolerate.

This is practically unfathomable. The main problem is the piling up of multiple negatives, since the human mind appears to be limited in its ability to understand negation to about two or three per thought. Fortunately, double negatives cancel out, and formal logic provides techniques for reducing the number of negations.

What was Laski trying to say? In the essay, Orwell never explains the sentence, writing only that:

Professor Laski…uses five negatives in 53 words. One of these is superfluous, making nonsense of the whole passage, and in addition there is the slip alien for akin, making further nonsense, and several avoidable pieces of clumsiness which increase the general vagueness.

I'm unsure how Orwell came to a count of five negatives in the sentence, as I count at least six. There are only four "not"s, so I assume that he was counting either the "un" in "unlike" or "nothing" as an additional negation, but both should be counted.

I don't know how Orwell knew that "alien" was supposed to be "akin", but let's assume that he was right. Can you untie the "not"s in Laski's sentence, producing a translation that is understandable? Or was Orwell right that one of the negatives is "superfluous", rendering the sentence nonsensical?

Solution

Source: George Orwell, "Politics and the English Language", The New Republic, 6/17/1946.

Previous Puzzles:

CEMETERY RD NO EXIT
February 22nd, 2010 (Permalink)

The Undiscovered Country

I've complained previously about the tendency of the media to offer a skeptic a minute or two on a program, or a sentence or two in an article, when covering pseudoscience. Michael Shermer recently played this role on an episode of Larry King's show dealing with "near-death experiences", as he recounts in the latest "Skeptic" column in Scientific American. I don't know why shows such as King's bother with such "token skeptics" since, rather than providing balance, it usually just highlights how one-sided the shows are.

For some strange reason, near-death experiences are often treated as evidence for an afterlife, or for what an afterlife will be like. However, there's really no reason to see them that way, as opposed to taking them as evidence of what hallucinations people experience when the brain is deprived of oxygen in the process of dying. Some of the accounts claim that the dying person learns information that they could not have acquired in any normal way, but that's still no more evidence of an afterlife than of some kind of "psychic" perception triggered by nearly dying.

This topic is muddled by both the ambiguity and the vagueness of the concept of "death". In the past, most people considered death to be the stoppage of the heart, breathing, consciousness, and all movement. However, if you define "death" in these terms, then many people have "died" and come back to life again. If, in contrast, you define "death" as the cessation of brain activity―often called "brain death"―then a person who appears dead may not be dead at all. Shermer discusses an example:

The same definitional problem arose when guest host Jeff Probst (of Survivor fame, fittingly) introduced the football referee: "A man died on a football field seven years ago and came back to life." Gupta added that he "was dead for two minutes and 40 seconds." When I was asked for an explanation, I said: "He wasn’t dead! … He was in a near-death state." In fact, moments after collapsing, the ref had his heart restarted by an automated external defibrillator. There was nothing miraculous to explain.

Presumably, when Gupta said that the ref "was dead for two minutes and 40 seconds", he was using the word "dead" in the sense of heart-stoppage. However, the ref was almost certainly not brain dead in less than three minutes. As Shermer says, there's nothing miraculous about reviving someone whose heart has stopped for a few minutes, whether you call the person "dead" or not.

Moreover, no matter how you define "death", it's a biological process that, like other such processes, does not occur in an instant:

Dr. Gupta started us off by recalling that when he was in medical school the residents were taught to mark the time of death to the minute, when death can often take anywhere from a couple of minutes to a couple of hours to occur, depending on the conditions.

In other words, "death" is a vague concept and the boundary between life and death is fuzzy. For this reason alone, there will be people who have experiences where we cannot tell whether they were "really" alive or dead.

So, what does all this say about an afterlife? Precisely nothing, as far as I can see.

Source: Michael Shermer, "Surviving Death on Larry King Live", Scientific American, 3/2010

''TREMENDOUS!''
February 19th, 2010 (Permalink)

A "Tremendous!" Contextomy

Here's something I've never seen before. An ad for the new movie Blood Done Sign My Name has the single word "tremendous", followed by an exclamation point, and enclosed in quotation marks. So, it appears to be a critic's blurb, but it's not attributed to any critic or publication. Assuming that it's taken from an actual review of the movie, there's no way to check whether it's being quoted misleadingly. However, how do we even know that it comes from a review of the film? For all we know, the ad could be quoting the dictionary. Or, perhaps the ad writer muttered the word under his breath as he wrote the ad, then quoted himself. This has to be some kind of record-setting contextomy.

Update (2/26/2010): Another ad for the same movie has the blurb:

"TREMENDOUS! POWERFUL & RIVETING!"
-MOVIEWEB

The original ad discussed above followed the single-word blurb "TREMENDOUS!" with a blurb attributed to Movieweb, which led me to think that the "TREMENDOUS!" blurb might also have come from the same source. However, a search of Movieweb did not reveal any use of the word "tremendous" in reference to the movie, so I assumed that this was not meant to be the source of the blurb.

The only occurrence of the word "tremendous" in a review of the movie on Movieweb that I can find is the following sentence by reviewer Harvey Karten: "In 1964, President Johnson, who had more influence with the Congress than the current chief executive, got a major civil rights act passed far reaching and had tremendous long-term impacts on the whole country. [Sic]" So, it appears that this is an ordinary if rather extreme contextomy, after all.

The word "riveting" also occurs in the same review in the following context: "You wouldn't know this by watching Jeb Stuart's riveting film, one based on a real case in Oxford, North Carolina." There's no problem with that part of the blurb, since Karten is referring to the film, and not the impact of LBJ's civil rights legislation.

The word "powerful" does not occur in Karten's review, but does occur twice in the one other review of the movie I could find on the Movieweb site. However, neither occurrence refers to the movie directly, but to its "story" and "material". The fact that the ad takes words from two different reviews and combines them into a single blurb presumably explains why the blurb is attributed only to Movieweb, and not to an individual reviewer. This is another practice I've never seen before, and it certainly opens up possibilities for some creative contextomies!

Sources:

February 12th, 2010 (Permalink)

"Where's Your Argument?"

Manchester Metropolitan University in Cheshire, England has a conference on informal logic, critical thinking, and argumentation called "Where's Your Argument?" on April 12th and 13th. It has a terrific lineup of speakers, including:

  • Frans van Eemeren on the Pragma-Dialectical approach to argument. Van Eemeren, together with Rob Grootendorst, is responsible for this influential theory of argumentation.
  • Steven Poole will speak on unspeak, if that's possible. Regular readers of The Fallacy Files may remember that his book was my first, abortive, attempt at a "book club".
  • Jamie White, author of the excellent Crimes Against Logic will speak on bad thoughts and worse policies.

The conference is free, but requires registration by April 1st―I hope that's not some kind of joke, as I'm not sure whether April Fool's Day is celebrated in England. In any case, you'll probably feel like a fool if you don't register by that date and then try to attend the conference. If you want more information, you can email the conference, or visit its website.

February 11th, 2010 (Permalink)

Headline

Rare snow bears down on Deep South

Polar bears in dixie? I blame global warming!

Source: Dan Gilgoff, "Rare snow bears down on Deep South", CNN, 2/12/2010

February 10th, 2010 (Permalink)

What's New?

The fallacy of Overgenerality! This is a highly general fallacy―though hopefully not overly general―and I add it mainly as a place to hang subfallacies. However, it also provides an opportunity to explain the difference between three concepts that are often confused: overgenerality, vagueness, and abstraction. Overgenerality is not yet represented in the full Taxonomy, but its branch can be seen at the top of the entry. In the future, such branches will replace listings of Type, Subfallacies, and Sibling Fallacies in the fallacy entries.

February 3rd, 2010 (Permalink)

Headline

Gator Attacks Puzzle Experts

Thankfully, there are no alligators in this part of the country. The above headline was taken from The New York Times Magazine's most recent "On Language" column. According to the column, such amphibolous headlines have been dubbed "crash blossoms". The name is taken from another example: "Violinist Linked to JAL Crash Blossoms". I don't much care for the name "crash blossoms", and I doubt it will catch on, but you never know. Of course, as any reader of The Fallacy Files knows, I do like crash blossoms and use them here under the rubric "Headlines". If you like them too, then read the whole thing.

Source: Ben Zimmer, "On Language: Crash Blossoms", The New York Times Magazine, 1/27/2010

February 1st, 2010 (Permalink)

Untie the Nots, Part 3

You sign up for an internet service but after less than a month decide that you don't want to continue it. However, the agreement you signed contains the following puzzling statement:

You will not be charged your first monthly fee unless you don't cancel within the first 30 days.

Can you cancel the service without paying the first monthly fee? To find the answer, determine which of the following statements has the same meaning as the puzzling statement:

  1. If you cancel within the first thirty days, you will be charged your first monthly fee.
  2. You will be charged your first monthly fee unless you cancel within the first 30 days.
  3. You will be charged your first monthly fee only if you cancel within the first thirty days.
  4. If you cancel within the first thirty days, you will not be charged your first monthly fee.
  5. If you don't cancel within the first thirty days, you will be charged your first monthly fee.

Solution

Previous Puzzles:

January 30th, 2010 (Permalink)

Headline, Too

"Avatar" Becomes Highest-Grossing Movie

Here's the "Numbers Guy" on "Avatar"'s record-breaking box office:

Barely a month into its theatrical run, "Avatar" set a record for world-wide ticket sales, topping $1.85 billion. That is a reflection of its wide popularity, and also a reminder of the quirky way that Hollywood crowns champions. In recent decades, the agreed-upon benchmark for movie dominance has been box-office revenue, unadjusted for inflation. That means "Avatar," like the previous all-time leader, 1997's "Titanic," and prior box-office kings benefited in part from favorable comparisons. Since tallies of ticket sales aren't adjusted for inflation, rising ticket prices have helped pave the way for a number of more-recent films, including "The Dark Knight" and "Transformers," to land near the top of box-office rankings. Of the top 25 grossing films of all time on Hollywood.com's U.S. box-office ranking, 18 were released in the past decade. Adjust the totals for higher admission prices mainly due to inflation, and "Avatar" would be the only one of those 18 to make the list―at No. 24, as of Thursday.

If inflation didn't exist, Hollywood would invent it.

Sources:

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