The "fallacy" vice

Y'know how it's sometimes little things that wind you up? Well, one thing that really irritates me is the habit libertarians have - it seems to be mainly libertarians - of accusing their opponents of fallacious reasoning, when in fact there seems to be no such fallacy.
First, a matter of definition. There's disagreement here, but I understand "fallacy" to mean an error of logic, of deduction - that is, something that is demonstrably, proveably wrong. A fallacy, then, is just one sort of bad argument, not a synonym for "bad argument."
Johnathan Pearce, criticizing a letter to the Times, illustrates what I mean. He writes:

The writer assumes as a matter of course that "inter-generational inequality" - however defined - is of itself a bad thing.

But a bad assumption is not a fallacy, an error of logic. It's just something you can argue with.

Another fallacy here is the idea that when people inherit wealth, the money solidifies in great, useless lumps and therefore other, less fortunate people are denied access to the good things of life. But this is the zero-sum fallacy.

Again, "fallacy" is the wrong word. Sometimes, money can indeed be used to deny others access to the good things of life. For example if it's used to buy one of the few houses in an area with a nice view, the higher prices of such houses act to deny others access. There are such things as positional goods. The difference between Johnathan and the letter-writer is about how common these are - a matter of fact, not logic.
My gripe here is not with the substance of Johnathan's argument. It's with his misuse of that word "fallacy". If he meant "bad argument", "contentious and unargued assumption", or "probable factual error", I'd have no problem.
There are lots of ways of arguing badly, not all of which are fallacious.
Why does this wind me up? It's not because I'm a pedant. It's because I don't like the belief which seems to underpin it.
In accusing your opponents of fallacies, you give the impression that political argument is merely a matter of logic, and that if only we could all think clearly, we'd all agree. This is surely not the case.
Which raises a question. Am I right in thinking that libertarians are disproportionately likely to (wrongly) accuse others of committing fallacies? If so, why do they do so?

Comments

[EddyP]

Libertarians certainly are more likely to accuse others of doing this. This is because we believe others are much more likely to be arguing from assumptions which are, at the least, debatable; yet at the same time they tend to act as if these assumptions are a given. The desirability of egality is the big one.
Libertarians regard their central assumption, freedom from interference unless harm is being caused to others, as stronger and more intellectually defensible.
The main reason why libertarians will so readily accuse people of fallacious argument is because of the way they think ideas of egality and welfare have been politically sold to the populace rather than logically reasoned out by people.

[JH]

fal·la·cy (fāl'ə-sē)
n. pl. fal·la·cies

1. A false notion.
2.A statement or an argument based on a false or invalid inference.
3. Incorrectness of reasoning or belief; erroneousness.
4. The quality of being deceptive.

[Alteration of Middle English fallace, from Old French, from Latin fallācia, deceit, from fallāx, fallāc-, deceitful, from fallere, to deceive.]

Not sure whether I agree that the definition of fallacy should be as narrow as you suggest.

[Marcin Tustin]

It's probably because libertarians are disproportionately intelligent, and technically educated people. The curricula of technical studies are typically not designed to give an understanding of history, including the history of thought, and the differences of value that exist between people. Instead any reference to history is in the form "...but we know better now," and presents progress as greater scientific and applied technical achievement. This can easily be transferred to anything else that is seen to be a product of the enlightenment, such as voting, free markets, or claiming that your opponents can't think properly, and are worse, rather than just different.

[Chris]

I'd say it's more a feature of internet debate than specifically libertarian, but of course there's the whole 'bloggertarian' thing so maybe the two sets collide. I agree with EddyP's suggestions above and also would add that using 'fallacy' - or even better, a 'named' fallacy - inexplicitly as a synonym for 'mistake' or 'error' is an exercise in rhetoric. Through ambiguity over which meaning it represents, the specific reference to logical error or the general, it can create the assumption that the writer is more rational and logical than the person being criticised without recourse to actual strength of argument. I believe it's similar to beginning with 'As a member of the reality-based community...'

My personal bugbear, for what it's worth, is the overuse of 'straw man', which seems to now be brought out any time there's an attempt to legitimately extrapolate consequences or merge a range of authors into a composite. I have no idea whether libertarians do this more.

[William McIlhagga]

Fallacy doesn't bug me, but what really gets me annoyed is 'category error'.

[dearieme]

Ooh, I get so fucking fed up when people blether on about "begging the question". I can only assume that they are soccer supporters.

[:-) Andrew]

I totally refute that.

[Matthew]

Ah,no. Straw man is about the most useful blog argument, as it's almost always relevant. Even on this blog, probably the least offender of the well known ones, we get absurd attacks on the tax and benefit system that don't stand
up.

[Nigel Sedgwick]

I reached for the dictionary, as presumably did JH (see above), and found the complaint unsubstantiated.

Clearly Johnathan Pearce is using definition 1 from JH's dictionary.

But is Chris's posting a fallacy according to definition 4, or just based on a false notion as to the meaning of fallacy (so definition 1)?

Best regards

[chris]

Sorry, chaps. I'm not happy about using "fallacy" in the wider sense. It's tremendously useful to have a word that means "error of logic" as distinct from "mistake" generally. If we use "fallacy" loosely, we lose a useful bit of language.
Why would anyone want to use the word "fallacy" - in the way Johnathan does - when "mistake" or "error" would do just as well?

[Nigel Sedgwick]

@Chris: ah; noted.

But the English language (one of the richest in the world) is not the private property of any one person, nor of those of any one political persuasion, nor of any one other group (eg academic philosophers), except perhaps within their own circle.

Still, this blog is your private property and I'll respect that as far as I can, not least by only using 'fallacy' here according to definition 2 and the first part of 3.

Best regards

[Jon Heath]

But Chris, we already have a word to describe arguments that contain an error of deductive logic: it's "invalid". The problem with defining "fallacy" as narrowly as you would wish is that many long-standing fallacies are informal, which makes their definition and identification a contentious issue. For example, is the "naturalistic fallacy" a true fallacy or an enthymeme?

[Eric H]

The reason it's called the zero-sum fallacy is because there is indeed a fallacious line of reasoning behind it:

A has more than B. Therefore, A has taken from B.

Perhaps in the case cited, *the* "zero-sum fallacy" is the wrong argument for the reasons given, but there is a good reason to call it a fallacy.

Did I add anything, or did I just restate comments already made?

[prefabrik evler]

Straw man is about the most useful blog argument, as it's almost always relevant. Even on this blog, probably the least offender of the well known ones, we get absurd attacks on the tax and benefit system that don't stand up.
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