"The Fallacy Fallacy"

An excerpt from Maarten Boudry (Persuasion):

My doubts [about the value of focusing on logical fallacies] began when I was still in academia, teaching critical thinking to philosophy students and science majors alike. Fallacies are a favorite chapter in such courses. In some ways, they are ideal teaching material: they come in tidy lists and seem easy to apply. Many trace back to Aristotle and still parade under their Latin names—ad hominem, ad populum, ad ignorantiam, ad verecundiam (better known as the argument from authority), the slippery slope, affirming the consequent, and so on.

So I dutifully taught my students the standard laundry list and then challenged them to put theory into practice. Read a newspaper article or watch a political debate—and spot the fallacies!

After a few years, I abandoned the assignment. The problem? My students turned paranoid. They began to see fallacies everywhere. Instead of engaging with the substance of an argument, they hurled labels and considered the job done. Worse, most of the "fallacies" they identified did not survive closer scrutiny.

It would be too easy to blame my students. When I tried the exercise myself, I had to admit that I mostly came away empty-handed. Clear-cut fallacies are surprisingly hard to find in real life. So what do you do if your professor tells you to hunt for fallacies and you can't find any? You lower the bar. To satisfy the assignment, you expand your definition….

In 2015, I published a paper in the journal Argumentation with two colleagues arguing that fallacy theory should be abandoned. Here is its crux: every so-called fallacy closely resembles forms of reasoning that are perfectly legitimate, depending on the context. In formal terms, good and bad arguments are often indistinguishable. Worse, there is almost always a continuum between strong and weak arguments. You cannot capture that gradient in a rigid formal scheme. As my friends Hugo Mercier and Dan Sperber succinctly put it in The Enigma of Reason: "most if not all fallacies on the list are fallacious except when they are not." …

Read the whole thing here.

Comments

[dwb68]

Yeah the problem with teaching fallacies is that sometimes a slope really is slippery.

add: the focus on persuasive argument is misdirected. There are facts and then there are several interpretations of those facts, some of which are parsimonious. Sometimes the most parsimonious explanation is also the least persuasive. God does not play dice with the universe, and yet he does

[Bubba Jones]

I think largest disagreements typically revolve around different priorities.

Is the disagreement really about the existence of global warming? Or is it about the cost-benefit of specific actions?

Setting aside personal benefits and motivations...

[dwb68]

The largest disagreements involve the smallest stakes. See: Academia

Some will tell you that climate science is based on the world's longest running "post hoc ergo propter hoc" fallacy.

[Bubba Jones]

The reality is that most people rely on deeply flawed reasoning.

Even the ones pointing out fallacies.

In the real world, it's usually more productive to try to understand what it is the person really wants, and why.

[Stupid Government Tricks]

Trying to understand what someone wants is made harder when they themselves supply crappy arguments. It can be an opening to try and pin them down, make them narrow their focus until you get something arguable, but it's a tedious enterprise and they seldom appreciate being tricked into contradicting themselves.

[Bubba Jones]

If they don't know what they want, why argue about it?

If they do know what they want, does it really matter why?

Argument is almost never persuasive.

That's why lawyers rely so heavily on procedural pedantry.

[Stupid Government Tricks]

Leaving spurious-but-plausible-sounding posts unanswered leaves fence-sitters thinking it just might be true, since no one disputes it. The point, then, is to make sure the fence sitters realize there are other sides to the argument.

[Flatulus]

"...every so-called fallacy closely resembles forms of reasoning that are perfectly legitimate..."

Yeah, that's why properly identifying fallacies is so important. Left unidentified, fallacies can easily masquerade as valid arguments. The difficulty of the task is not an adequate reason to abandon it.

[gVOR08]

^^^^^

[bernard11]

My thought exactly.

Teach them how to distinguish actual fallacies from arguments that sound the same, but are not fallacies.

[Brett Bellmore]

To be precise, most logical fallacies are perfectly good heuristics.

Bob has murdered his last three room mates. Should you sublet to him? It would be the fallacy of induction to say that he'd murder you if you did!

[dwb68]

Sure, Bob killed his last three roommates. But we have a new warden in the prison now.

[MollyGodiva]

If he students turned paranoid, then he was not teaching the material correctly.

[Lee Moore]

I expect he was teaching it correctly. After all you can construct canonical examples of these fallacies which really are fallacious and which students ought to understand clearly.

The trouble comes with actual examples you come across and it requires actual thought to decide whether they are or are not fallacious.

I expect they didn’t turn paranoid - I expected they just remained lazy. Humans don’t do logic naturally, it’s hard hard labor. Humans do heuristics naturally. Evolution is a “good enough” system.

[MaddogEngineer]

Certainly descriptive of the comments section on the blog.

[wvattorney13]

IMHO, the problem is that pointing out that an argument is a logical fallacy is not the same as proving that the conclusion is invalid or false. It is stating that the arguer has not proven his point.

Sometimes people are standing at the top of the slippery slope. Sometimes a person with knowledge is giving an informed opinion. Sometimes a criminal will murder again.

But for these "sometimes" to be true the person putting forth the argument must do more than rely on these logical fallacies. It is correct for people to point them out and make the person show their work.

[SRG2]

In Bayesworld - like Wayne's World but not quite as funny - many claimed fallacies are nothing of the sort. As Brett noted, they're heuristics.

[Sarcastr0]

Fallacies are often employed, even unconsciously, when someone wants something to be true, but can't get there.

It's worth pointing that out, and telling them to show their work better.

[Brett Bellmore]

And fallacies are often cited, when someone wants something to be false that's probably true, and so confuses "logically possible that it's false" with "false".