Impure Motives (Part 16 of Fallacies/Red Herrings)

A short installment this week. Part 16 of Red Herrings covers still more responses to arguments that distract from the argument rather than address it directly. This week we cover the appeal to motive.

Appeal to Motive

Scientist A says that man-made climate change is a real threat. Scientist A is a candidate for tenure at a well-known university, and the head of his department believes the same thing. This means that Scientist A’s motives are impure, and therefore his argument is false.

This is the appeal to motive, another subcategory of the argumentum ad hominem. Its special feature is that it’s only necessary to show that there is a possibility of a motive, however small. What’s missing is proof that (a) the motive actually exists, (b) if it does exist, it played a role in formulating the argument and conclusion, and (c) any other proof or evidence offered is ipso facto invalid.

It’s related to general claims of conflict of interest. In the run up to the Supreme Court hearings on the Affordable Care Act, accusations of conflict of interest have been leveled at three justices, two conservative and one liberal. Showing the potential for a conflict of interest isn’t the same thing as demonstrating that the votes of these justices is necessarily corrupt. In the particular instance, it’s more likely the case that the predispositions of the justices predate the events and actions leading to the charge.

And Brutus is an Honorable Man (Fallacies Part 4)

Red Herrings



Red herrings are responses to an original argument that don’t address the substance of the argument — they’re distractions. The various forms of ad hominem are attempts to discredit the argument by discrediting the arguer. But what about the reverse? What if the claim is that the argument is true because the arguer is an authority?

Argument From Authority

In the argument from authority, we claim that a statement is true because of the person who said it. The general form of this argument goes thusly:

1. Person A makes claim C.
2. Person A has particular authority or credentials in the area of claim C, or is a unique position to know the truth about claim C.
3. Therefore, claim C is true.

It goes by three different Latin names, each of which gives a slightly different flavor to the argument.

Argumentum ad verecundiam is generally translated as “argument from respect,” but verecundiam really means modesty or shyness, a cynical formulation by the phrase’s creator, John Locke. “When men are established in any kind of dignity, it is thought a breach of ‘modesty’ for others to derogate any way from it, and question the authority of men who are in possession of it.” 

On June 3, 2011, Sarah Palin famously spoke of Paul Revere, saying in part, “He…warned uh, the British that they weren't gonna be takin' away our arms….” The resultant fight that broke out on the Paul Revere Wikipedia page is about power. The criticism of Palin was treated by her adherents as a form of lèse majesté — as if it were improper and unfair to do anything other than accept her formulation as fact.

Argumentum ad potentiam means “argument from power,” in which the temporal authority of the speaker is the evidence offered for the truth of the statement. That’s what Marc Anthony mocks when he says, “But Brutus says he was ambitious. And Brutus is an honorable man.”

The third version of argument from authority is ipse dixit, or “he himself has said it.” It’s simply a bare assertion, a statement offered without evidence or factual support. You are supposed to believe it purely on the word of the person making the statement. The rule, for example, that one must not end a sentence with a preposition comes from 18th century grammarian Robert Lowth — who made it up.

Of course, it’s not wrong to have your opinions and beliefs influenced by people with particular authority and education. In fact, it’s hard to see how we could avoid doing so. We don’t have the time to learn everything ourselves, and in some cases we don’t have the capacity, tools, or resources. The fact that a given authority believes something can be a reason for us to believe it ourselves, at least as a provisional hypothesis until something better comes along.

What it doesn’t do is constitute a formal proof. For a formal proof, you have to provide evidence of the proposition itself, rather than a list of the credentials of the person making the statement.

Pot, Meet Kettle (Fallacies, Part 3)

Last week, we began a survey of red herrings, responses to an original argument that don’t address the original issue, with argumentum ad hominem, discrediting an argument by attacking the arguer.

Ad hominem tu quoque

Tu quoque (“you, too”) is a subset of ad hominem in which the character flaw used to discredit the arguer is that the arguer has been inconsistent or hypocritical on the same subject in the past. There are several subsets:

Person A criticizes behavior B.
Person A has been guilty of behavior B.
Therefore, person A’s opinion is invalid.

Although Person A has been a hypocrite, that doesn’t mean A is necessarily wrong. As François de La Rochefoucauld famously observed, “Hypocrisie est un hommage que la vice rend à la vertu.” (“Hypocrisy is the tribute vice pays to virtue”) A person can indeed be guilty of behavior and legitimately deplore it at the same time. In my own case, it’s fair to say:

Michael complains about ad hominem attacks.
Michael has committed ad hominem attacks in the past.
Therefore, Michael’s complaint about ad hominem is invalid.

It’s fallacious because our individual hypocrisies and failures of consistency don’t prove we’re wrong; sometimes they can even be evidence that our propositional ideal is more correct. Ad hominem attacks are a bad idea, whether or not I have been consistently able to refrain from them — in fact, the fallout from my own violations has tended to reinforce my belief that it’s a bad idea.

Another version of tu quoque is claiming inconsistency. In this version, the form is:

Person A makes claim C.
Person A has previously made claims that are inconsistent with C.
Therefore, claim C is false.

In 2008, Bill Gates said, “People everywhere love Windows.” In 1987, however, Bill Gates said, “I believe OS/2 is destined to be the most important operating system, and possibly program, of all time.” Although the first statement is arguable (he said as he types on his Macintosh), offering the second statement as a rebuttal to the first is a logical fallacy.

There are two legitimate uses of tu quoque arguments. The first is legal, the maxim that you cannot approach the courts of equity with unclean hands. If you fail to live up to your obligations under a contract, you may not be able to prosecute a claim that the other side has also failed, as long as their failure to perform is linked to your failure.

The other legitimate use of tu quoque is to discredit someone as a role model for a position. If Person A has built a political career on being a faithful marriage partner but turns out to be actively polyamorous, it’s perfectly legitimate to argue that Person A is no longer credible on the subject. That’s different from arguing that Person A’s infidelity proves that faithfulness in marriage is not a good idea.

The expression “pot calling the kettle black” can also describe some forms of tu quoque arguments. Another famous example can be in the punchline to the famous 1960s era Russian joke, “А у вас негров линчуют.” It goes like this. An American and a Soviet car salesman are arguing about which country makes better cars. The American asks, “How many decades does it take an average Soviet man to make enough money to buy a Soviet car?” The Soviet answer? “And you are lynching Negroes!”

Red Herrings and Other Fishy Arguments (Fallacies Part 2)

Red herrings are responses to an original argument that don’t address the original issue. They are distractions, attempts to throw off any examination of the argument on its own merit. Red herrings can be used by both sides: by the attacker to undercut the original argument, and by the defender to undercut the rebuttal.

One large class of red herring arguments involves shifting the argument from the substance to the people involved. Ad hominem arguments attack the arguer. Ad baculum arguments use threats. Ad populem arguments count numbers. Ad Hitlerian arguments accuse one side of being Nazis, or at least Nazi-like.

Argumentum ad hominem

My great-great-great-aunt Molly Elliott Seawell is a minor figure in the history of American letters. (Her former salon on P Street here in DC is on the Register of Historic Places.) The author of forty-something books, mostly boy’s adventure with some Graustarkian romance, she was famously attacked by Walt Whitman over her 1891 essay, “On the Absence of the Creative Faculty in Women.”

Yes, you read it right. And she was quite serious. A virulent anti-suffragette, Seawell denied that women had any intrinsic creativity. When the obvious counter-example came up, Seawell dismissed her own work as meritless — she was, after all, obviously only a woman.

Ad hominem arguments take a characteristic of an opponent and use that characteristic to discredit the argument. A mere insult doesn’t qualify. For example, “That jackass Joe is wrong because his facts are in error” contains an insult, but the insult isn’t part of the argument: the argument is the claim that Joe’s facts are in error. No ad hominem here.

“Joe is wrong because he is a jackass” contains the same insult, but now it’s ad hominem because the evidence that Joe is wrong is that he is a jackass. Joe may indeed be a jackass, for all we know, but that fact alone doesn’t establish that he’s incorrect.

But what if it does? If the personal characteristic does disqualify someone’s argument, or at least lessen its potency, is it still ad hominem?

Some years ago, I was asked to read a manuscript purporting to prove that relativity was false, and that only a conspiracy of physicists either too stupid or too venal to face the truth was keeping the veil of deceit intact. The author had a journalism degree and had interviewed exactly one scientist, evidently his source for the Einsteinian hoax revelation.

Is it logically incumbent on me to go through the arguments in that book step by step to refute them, or can I simply look at the skimpy credentialing and sourcing and use that as logical grounds to dismiss his argument from serious consideration?

My own answer is yes. In the unlikely event the argument has merit, it will sooner or later convince others. If the argument shows up again, this time in more credible mouths, it will be time for me to reassess.

So the first question is whether the claim is true, and the second question is whether the if-true claim actually discredits the substance of the argument. Which brings us back to Molly Elliott Seawell. Her proposition is, “My work is not creative because I am a woman.” The proposition “I am a woman” is true. It’s also possible that “My work is not creative” is true — I myself am not impressed with her literary gifts. If both propositions of the argument are true, is not the whole argument true?

The problem here is “because.” You can’t assume such a connection. If you want to assert it, you have to offer proof, in this case, that there is not only a correlation, but a causation.

Properly, the burden of proof lies on the shoulders of the side that claims the linkage. If it’s a valid linkage, you ought to be able to prove it, not just claim it. What criteria measure creativity? Are those criteria objectively valid (or at least acceptable by both sides)? What is the actual distribution among women and men? If there are differences, are they statistically significant? Have alternate explanations and theories to account for any significant differences been explored?

That’s a high burden of proof, but it’s fair. If you argue against a proposition by arguing against the person, it’s your responsibility to prove it’s not ad hominem, and if you fail, the argument’s a fallacy.

To me, Seawell’s claim is clearly ad hominem because the claim that her womanhood compromised her creative mechanism is on the face of it ridiculous. It can’t be accepted at face value; the burden of proof weighs heavily against the proposition. But that’s not the way she saw it. Her world (and her books) were filled with subservient Negroes and noble white boys. That was the way of the world, and it thus meant the burden of proof fell on the other side. The general wisdom said that women were creatively inferior; she had popular opinion on her side. But that’s argumentum ad populem, a fallacy for another day.

Fallacies (a New Series in the Manner of Cognitive Biases) - Part 1

As a follow-up to my series on cognitive biases, here’s the start of a new one: a description of classical fallacies. For the purposes of this discussion, a fallacy is an opinion or position based on invalid reasoning. The conclusion itself may not be wrong, but the argument offered in support of it is wrong.

“He plays a doctor on TV; he endorses this medical product; therefore, the medical product is good” is fallacious not because the medical product being touted is necessarily not good, but because it’s ad verecundiam, an appeal to an authority outside the authority’s area of expertise. If the same authority made a statement about the profession of acting, however, it wouldn’t be ad verecundiam because the actor presumably has standing on the subject.

Just because the actor has standing, however, doesn’t constitute a final proof that the proposition is true. At most, it counts as an evidence point — but it’s a logically valid one.

For the list of fallacies, I’m starting with the list on Wikipedia. There’s another extensive list at The Nizkor Project.  The examples and discussion are my own.

Fallacies come in two basic flavors.

Formal fallacies, as the name suggests, are errors of form: regardless of the contents of the argument, or the truth of any of the statements, the argument is invalid on its face.  An appeal to probability is one such fallacy: the idea that if something could happen, it necessarily will happen.

There are subsets of formal fallacies. Propositional fallacies are structural errors in logic.  “It’s raining or it’s Tuesday; it’s not raining, therefore it’s Tuesday” is a propositional fallacy (affirming a disjunct). It may not be raining, but that doesn’t make it Tuesday.

Syllogistic fallacies also fall into the category of formal fallacies. “Some cats are black; some black things are televisions; therefore some cats are televisions” involves an illicit treatment of the minor term (you can’t assume that the set of televisions and the set of cats have common members because they share a particular color).

Informal fallacies are not fallacious because of their structure, but usually because of their content. Ad verecundiam and its kissing cousin ad hominem both use a personal characteristic to prove or disprove a proposition without establishing that the personal characteristic in question actually determines whether the conclusion is true or false.

I learned a lot doing the cognitive biases series, and I hope to learn a lot on this project as well. If you’ve seen any great examples of any of these fallacies, please let me know.