Ad Hominem

An argumentum ad hominem is any kind of argument that criticizes an idea by pointing something out about the people who hold the idea rather than directly addressing the merits of the idea. ''Ad hominem'' is Latin for "directed toward the man (as opposed to the issue at hand)". An alternative expression is "playing the man and not the ball". Some examples:

Ad hominem attacks are ultimately self-defeating. They are equivalent to admitting that you have lost the argument.

The ad hominem is a fallacy of relevance: when you fall into it, you're confusing two topics that are really distinct. The confusion dissolves when you point out the implausible connections that are implied: "So if I quit my job, then marketing would serve a valuable purpose?" "So if I never dropped any acid, then everyone could take heroin with no danger of overdose or brain damage?" The only way to make an accurate assessment of marketing or drugs is to actually look into marketing or drugs.

The ad hominem is not to be confused with various measures that are prudent to take when delegating cognition to others, such as checking people's credentials before relying on their testimony.

Also not to be confused with a number of other fallacies of relevance, like appealing to feelings and prejudices rather than intellect. There are fancy Latin terms for a lot of those, too; see:

Types of ad hominem

attack the person instead of the argument ("Only a cold-hearted Scrooge would cut this program!")

attacking the circumstances of the person ("How can you be against relaxing immigration policies. Your grandparents came over from Italy!")

tu quoque ("you, too")
AKA "practice what you preach." ("Why should I follow this Java style guide? You write pretty sloppy code yourself!")

We see #2 quite often in politics without failing to see it for what it is.

And #1 as well has been used to such a great extent that it is now impossible to find a candidate who won't promise anything and everything to any special interest group he can find. The preceding was brought to you by the AmericanCulturalAssumption.

Insulting remarks are not to be confused with the AdHominem

"How could you slam the car door on your nose? What a dolt you are!"

This is perhaps not a kind remark, but certainly slamming a car door on one's nose is good grounds for dolthood. The evidence supports the conclusion, and the conclusion is not confused with anything else.

"Your mother sucks army boots!"

An insult. Not much of one, but an insult. An expression of disrespect. Not an argument supporting or criticizing a conclusion, and therefore not possibly a fallacy.

"Anyone who thinks that work could possibly be enjoyable, in the face of all evidence, experience, and reason, is a psychopath! You hear me, a psychopath!"

Not an effective way to enlighten the benighted, but not an argument against the enjoyableness of work--and therefore not possibly a fallacy. Rather, it's a change to another topic: an investigation into the psychological causes of the belief that work is enjoyable. A hypothesis is proposed, kicking off the new discussion. The person on the receiving end of this rant does not share the premise of the investigation, so further conversation is likely to be fruitless, but that doesn't make the rant an ad hominem.

"Heinlein's 'argument' that human rights don't exist because they can be violated is a sick caricature by someone who has nothing but contempt for his opponents."

Again, not an ad hominem. It's an attempt (probably not successful) to get the reader to see Heinlein's argument in a new way, but notice that it does not take the accusation about Heinlein as a premise supporting a criticism of Heinlein's view of human rights. The reader is not expected to already agree with the accusation (this is essential when persuading by ad hominem), and the author was presumably led to make the accusation because of his evaluation of Heinlein's argument, not the other way around. The author is explaining what gives rise to arguments like Heinlein's, and thereby helping the reader grasp his (the author's) worldview. Logically impeccable. However, if the author expects this statement to persuade all by itself, or demands that his view be rebutted before he gives support for it, he is ShiftingTheBurdenOfProof illegitimately.

Notice that the examples given in the opening are not insults.

Sinking to the level of ad hominem

From WageSlave:

The last time I checked, you are not in danger of life or limb when "talking back" to an employer.

Check again. I guess you've never seen the typical police response to a workers' action. Does the term "strikebreaker" mean anything to you?

Dude. I'm really trying not to sink to the level of the AdHominem argument here. Have you ever seen a real labor strike? I have. I remember several periods in my childhood where both of my parents were no longer receiving paychecks for weeks or months because the union was on strike. I remember the literal belt-tightening that occurred as a result of that. I also remember not having Dad home because he was scheduled to walk the picket lines night after night.

The italic author did not commit an ad hominem. He was merely condescending and sarcastic, and tossed in a RedHerring (since responses to strikes are a different topic than talking back to one's employer). Since "talking back" is an example of "a worker's action", it's not a RedHerring at all. The roman author responded by sinking to the level of ad hominem. The response tries to counter the premise of an assumed ad hominem argument: "I have too been on that side of the fence." By responding in this way, you grant the legitimacy of ''ad hominem'' reasoning. Just think of the implied connection: if the author's father hadn't walked a picket line, would that show that U.S. employees really are in danger of life and limb for talking back to their bosses?

This is nonsense; the italic author questioned the roman author's relevant knowledge, and the roman author responded with relevant assertions. I suggest that you refer to authoritative works such as T. Damer's "Attacking Faulty Reasoning: A Practical Guide to Fallacy-Free Arguments". (And if you think that's an ArgumentFromAuthority, you should definitely read the book, which distinguishes between valid and fallacious appeals to authority.)

Of course, this is a good reason to avoid condescension and sarcasm in conversation. It tends to provoke this kind of illogical response even from intelligent, well-meaning people. It spoils the conversation. In short order, we saw two fallacies of relevance: a RedHerring and an AdHominem rebuttal. Condescension and sarcasm are not to be confused with the illogic they spawn, though.

Perhaps it is wise to avoid the sort of pedantic condescension you display here.

The ad hominem is a fallacy, not a foul

Interestingly, people apologize for an AdHominem, but they don't apologize for a PostHocErgoPropterHoc or AdVerecundiam, which are equally fallacious. This is due to a very deep confusion: between logic and conversation.

A fallacy is something that happens within a mind. It's a confusion, a mental misstep, whereby the mind moves away from truth, or at least the best it can do given the available evidence. Thinking is best when it's logical. Fallacies are ways that thinking strays from this.

A conversation is two or more people talking. A conversation about ideas, such as a debate, is cooperative thinking. You each try to learn from the other and enlighten the other. You try to stimulate logical reasoning in the other person's mind. At least, that's what happens in a good conversation. In a bad conversation, people see each other not as collaborators but as adversaries. Their purpose is not mutual enlightenment, but winning. This leads to all sorts of unfortunate concepts, like the idea of making it a fair fight. That in turn leads to rules, and rules lead to the concept of a foul. I brought in hearsay, or I didn't meet some "objective" standard of proof, or I didn't cite the proper authorities, or I made a wisecrack. The penalty for a foul seems to be that you must apologize, or be thought of as a cheater.

Don't confuse these things. Logic is the study of how the faculty of reason moves toward or away from truth. Conversation is talk. The reason to avoid insulting a person you are conversing with is not because it's illogical or unfair, but because he is a person. In addition to making the conversation unpleasant, it also tends to excite the parts of the mind that interfere with reason. When people do not feel respected, they have a tendency to seek revenge. Say, by humiliating you by making you look or feel stupid. They'll ignore or distort anything insightful that you say, because listening to it doesn't serve the purpose of revenge. If you want to have a good conversation, don't push that button. You'll find that both your and your friends' reasoning is less tainted with ad hominem. You might even have more friends.

The ad hominem in rhetoric

A word of warning to any would-be applied logicians out there: while the ad hominem leads to bad judgement and ruin, it has great persuasive power. (I refer here to genuine ad hominems, not insults.) If you're on the receiving end of the examples in the first section above, the other person has just spanked you publicly. The same applies to all the other fallacies named in classical and medieval times.

The way to counter a material fallacy, as illustrated above, is to expose the false connection implied in the fallacy--to distinguish what was confused. However, the ad hominem is particularly nasty because it taints anything that you say from then on. After the ''ad hominem,'' most people will hear anything you say as just a desperate rationalization, no matter how logically sound or factual. They won't hear you anymore. The fallacy, skillfully applied, is like cutting off your microphone.

The ad hominem exploits our meme-filtering cognitions: it moves such irrelevant considerations as one's position in the social hierarchy into place to block out genuinely relevant facts. It takes you down a notch in the social hierarchy so no one feels like they need to listen to you anymore. One of our own, intelligent, cherished Wikizens even started a page (ConsiderTheSource) in which the ad hominem is touted as a good reason to not take an idea or a person seriously--a very explicit (and favorable!) description of the ad hominem as a tool of disrespect.

Watch out for this thing. It's a powerful poison, no one is immune, and probably the majority of humanity will never understand what an ad hominem is or why it's bad. That includes people who use the term to criticize what other people say (usually just as a synonym for "insulting remark").

Immunity to the ad hominem pays off

A mother brought her son several hundred miles to see Gandhi. "I keep telling him not to eat sugar, but he won't listen to me. But he admires you and he'll listen to you." Gandhi said ok, and asked the mother to return with her son in a week. The mother was a bit nonplussed, but she made the long trip home and then made the long trip back the next week. "Ok, here we are again. Now will you tell my son to stop eating sugar?" And Gandhi says, "Sure. Kid, stop eating sugar." Now the mother is furious. "That's it? Why couldn't you have said that last week?" And Gandhi says, "Because last week, I was still eating sugar."

Are the people in this story engaged in the worst sorts of AdHominem and AdVerecundiam confusions? Yes! But the kid stopped eating sugar. (Or so the story goes.)


AdHominem is only a mistake in the context of deductive reasoning and logic. If, however, Joe and I are having a debate and I am able to effectively destroy Joe's credibility with an AdHominem attack, it can only be because Joe's credibility was somehow susceptible to that destruction. It is not enough for me to say "Joe is a twit; don't listen to him". But if I say "Joe is a marketing boob; don't listen to him" and Joe is in fact a marketing boob and that's relevant to what is being debated, then Joe's piteous cries of 'AdHominem' don't carry much weight. --AndyPierce

The point is, it's not relevant. That's why it's called a fallacy of relevance. If Joe is a marketing boob and he gives a cogent argument that marketing serves a useful purpose, the fact that this cogent argument is coming from a marketing boob is irrelevant. If a Ouija board made the argument, it would carry exactly as much relevance as if Gandhi said it. The source of an idea becomes relevant only when delegating cognition to others: when accepting their testimony--either reports of observations or relying on their expertise. Hence the proviso above. (See my remarks on ConsiderTheSource.)

But yes, as the explanations above indicate, crying "AdHominem" doesn't carry much weight with most people, even when a real AdHominem has just gone down. In fact, it only makes you look like more of a wuss.

Currently (early 2001) the phrase is enjoying a popularity that borders on the faddish... unfortunately with a distorted meaning, more or less synonymous with "you have no right to call me a dirty so-and-so, you dirty so-and-so; that's AdHominem, so there".

Where are you finding this?

As per Andy's remark above, by the time a discussion has degenerated into name-calling, the phrase is no longer appropriate, since the "fallacies of relevance" only apply in the narrow context of arguments with a logical structure. It reflects poorly on the Wiki community as a whole when the phrase is used as an easy justification for lack of same.

''It can also be used in less structured arguments, such as legislative debates. And the logical context isn't very narrow. Most coolheaded arguments are logically structured at some level.''

BTW, every argument has a logical structure: this, so this. It's not always stated explicitly, but it's always there. Fallacies of relevance confuse the issue. For example, confusing the topic of "is sugar bad for you?" with "does Gandhi eat sugar?" The solution to a fallacy of relevance is always to distinguish the topics.

It is you who are confused. Gandhi stopped eating sugar so that he would be in a better position to convince a child that eating sugar was bad; he (an accomplished lawyer) did not believe that whether he ate sugar had a bearing on whether sugar was in fact for the child.

On a wiki, AdHominem attacks are kind of pointless. If you consider the reader that comes by five years down the road, she doesn't know who any of the opponents are, let alone whether the personal accusations are true. Moreover, I doubt she ever cares about the particular ego drama that happened ever so long ago, except maybe out of quaintness. The worthiness of a wiki is to extract value from discussion. That's why a wiki is persistent. It's also why most wikis forget; so mistakes like AdHominem attacks can disappear with no hard feelings (memories). However, if you don't believe that, someone later can still come along and pick up the argument where you punched your opponent below the belt. So you only "win" temporarily. And you might lose in the long term when your argument gets shredded for being poor form without you there to defend it. -- SunirShah

Are you using "ad hominem" in the way criticized above, as a synonym for "insulting remark" rather than a logical fallacy, a mistake in reasoning (or a rhetorical move that guides others to make this mistake)?

No. Anything that derails an argument fallaciously is bad to the distillation of knowledge. Furthermore, above it's noted that AdHominem's are the worst because they ruin the rest of the discussion. Also, AdHominem attacks are often harbringers of real disrespect... or symptomatic. Address the root cause. The argument doesn't exist in a vacuum, at least not on a wiki. The same AdHominem may derail further discussions elsewhere. --ss

Hmm, I haven't seen much yet on Wiki that sounds like AdHominem. I've seen a lot of condescension, occasional outright insults, and some hysterical expressions of hostility, but very little attempt to rub the faults of an idea-holder off onto the idea itself. Could you point me to some examples? I, er, collect them. --bk

An very inoccuous example from KantsCategoricalImperative:

Kant's reasoning is obsolete, full of loopholes and nonsense. For example, Kant was a Christian theologian so he had an axe to grind against suicide. Kant used a ludicrous characterization of 'despair' to arrive at the conclusion he wanted despite the fact that suicide is universalizable. Given these facts, Kant's language isn't to be treated lightly.

Of course, the facts aren't. Suppositions as to the internal state of Kant's mind cannot be facts. Nonsense; it is factual that Kant held certain beliefs, and some of those beliefs are evidenced by his writings and behavior. Suppositions as to the internal state of Kant's mind can be factual just as suppositions as to the internal state of the Sun can be factual; mind states have no special epistemological status. (Although, I admit, it's probably a likely force.) His argument hasn't been refuted by appeals to background. Actually, most of the paragraph is informative. The first sentence is the most contentious.

I'll let you wade through the more damaging examples on Wiki yourself, but they usually get deleted. Moreover, most of the older content was non-argumentative as Wiki was used primarily to collect and organize personal experiences. Actually, one just from RecentChanges. See bottom of RecentChangesOnOtherWikiForums. That one also has AdVerecundiam. --ss

Thanks for the example, Sunir. You should have seen KantsCategoricalImperative a while ago, before I edited out the worst of the invective. It's interesting, though, that all of the above could be AdHominem or not, depending on what the point is. If the point is that imperatives can only be hypothetical, not categorical, then it's all AdHominem. If the point is that Kant was a twit, then it's not AdHominem. The context suggests that it's an explanation of how some article by Shandon Guthrie misinterprets Kant, but it doesn't do a very good of explaining that. The conversation there seems to have degenerated to a level of confusion for which is no name. --bk

Not to be confused with this attack, which is strictly AddHomonym?. And if you throw grits, it is an Ad Hominey attack.

Also known as Microsoft Standard Argument Technique:) -- ThaddeusOlczyk

Contrast ZenSlap for a bizarre twist on this.

See GodwinsLaw for another twist on this.

Scope Within Personal Attacks

The term is often mistakenly used to mean "an insult," especially by people who have just been insulted. E.g., "Theadic rixation is impossible under those conditions, you moron!" "Ah, so we descend to ad hominems, do we?"

It's often used interchangeably with "name calling". Although perhaps not technically accurate, most people still understand what is meant. If you feel an explicit distinction should be made, we can explore opening another topic for name-calling in general.

A distinction is being made between AdHominem and name calling. For example, the first example of an AdHominem on this page isn't name calling. In the other direction, name calling outside of an argument, isn't an AdHominem.

Ad hominem attacks are ultimately self-defeating. They are equivalent to admitting that you have lost the argument.

Some people use them as a punishment tool, not a communication tool. They may be thinking, "I'm going to punish this person for thinking poorly by calling them names". Whether it achieves that goal or not is another matter.

If it's used as a punishment tool, then it isn't an AdHominem. Some thing when used as a communication tool. It's only when used to support an argument that it becomes an AdHominem.

Contributors: BenKovitz, and many others who didn't sign their work (but are invited to)

See: FallaciousArgument, AttackIdeasNotPeople

CategoryJargon, CategoryCommunication

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