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The taxonomy of logical fallacies

This is totally, totally awesome. We should use this resource often -- maybe a Logical Fallacy of the Day, or something....

Taxonomy geeks unite! You have nothing to lose but illogic!

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Valley Girl's picture
Submitted by Valley Girl on

It is indeed very interesting- especially after I figured out that I could click on the chart for definitions.

I poked around. Found "wishful thinking" -


Psychologically, "wishful thinking" is believing something because of a desire—"wish"—that it be true. As a logical fallacy, Wishful Thinking is an argument whose premiss expresses a desire for the conclusion to be true.

Of course, this type of thinking seldom takes the explicit form of an argument from a premiss about one's belief to the conclusion that one's wish is true. Such bald wishful thinking would be patently fallacious even to the wishful thinker. Rather, wishful thinking usually takes the form of a bias towards the belief in P, which leads to the overestimating of the weight of evidence in favor of P, as well as the underestimating of the weight against. As in the case of the Example, it can lead to ignoring the evidence against a cherished belief, which is a case of one-sidedness. ~~

I note the misspelling of "premiss"- (premise) although thinking it through, "premiss" is a pretty good word in the context. LOL.

Shouldn't be too hard to find examples of "wishful thinking". I thought of Krugman, and went off to search his archives. Found this recent piece- interesting... it's actually pretty interesting. The World as He Finds It

Lambert, I dunno, but you're the expert here- does the statement that Obama is negotiating with himself qualify as "wishful thinking"? I say yes.

Krugman snippet (my bold)
~~And then there’s the tax-cut issue. Mr. Obama could and should be hammering Republicans for trying to hold the middle class hostage to secure tax cuts for the wealthy. He could be pointing out that making the Bush tax cuts for the wealthy permanent is a huge budget issue — over the next 75 years it would cost as much as the entire Social Security shortfall. Instead, however, he is once again negotiating with himself, long before he actually gets to the table with the G.O.P.~~

Submitted by lambert on

I'm the expert in rhetoric.

You're on your own, kid!

UPDATE Adding, that what makes the site special is that the tree links out to great content. Tree structures are a dime a dozen, but this is richer and more powerful.a

Submitted by gob on

I like that there's no pretense of an infallible test for a "soft" fallacy like wishful thinking. (For instance, Krugman's characterization of Obama strikes me as arguably wishful or not, depending on your views.)

Incidentally, "premiss" is an unusual but accepted spelling, especially in the technical literature of logic.

Submitted by lambert on

... on just that point. There needs to be evidence directly in the text, and not our projection into the psychology of the speaker. Otherwise, the attribution loses its force immediately!

Submitted by gob on

although it may not always be possible to get clear evidence. From the site:

wishful thinking usually takes the form of a bias towards the belief in P, which leads to the overestimating of the weight of evidence in favor of P, as well as the underestimating of the weight against.

Over/underestimating is not always so easy to see or prove.

That's why wishful thinking is classified as an informal fallacy. In short, it would be (extremely) nontrivial to write a computer program to detect it, even for arguments hand-encoded into a form the program could easily parse.

And that's why wishful thinking is so often committed by smart people. Like me, when I thought that having Obama as president would be miles better than having McCain.

Valhalla's picture
Submitted by Valhalla on

Could we get some sort of permanent link from Corrente to this site? It's yummy!

Valley Girl's picture
Submitted by Valley Girl on

I'd not seen this before. TY!!!!!

Transcript Mrs. Premise and Mrs. Conclusion visit Jean-Paul Sartre

Mrs Conclusion: Hello, Mrs Premise.

Mrs Premise: Hello, Mrs Conclusion.

Mrs Conclusion: Busy day?

Mrs Premise: Busy! I've just spent four hours burying the cat.

Mrs Conclusion: Four hours to bury a cat?

Mrs Premise: Yes! It wouldn't keep still, wriggling about howling its head off.

Mrs Conclusion: Oh - it wasn't dead then?

Mrs Premise: Well, no, no, but it's not at all a well cat so as we were going away for a fortnight's holiday, I thought I'd better bury it just to be on the safe side.

Mrs Conclusion: Quite right. You don't want to come hack from Sortonto to a dead cat. It'd be so anticlimactic. Yes, kill it now, that's what I say. ~~

Valley Girl's picture
Submitted by Valley Girl on

I didn't poke around enough.... re: premiss....

In an argument, a proposition presented as evidence for the conclusion. "Premiss" is a technical term in logic, which is frequently spelled "premise". Both are correct spellings, but I choose to follow the logician Charles Sanders Peirce in using the double-s spelling throughout the Fallacy Files. The reason for this is to avoid any ambiguity created by other uses of the word "premise".