Definition

Argumentum Ad hominem is discussion method to reply in a way to minimize value of opponent’s argument by discrediting him/her. Currently it’s included into Red Herring Fallacies group.

This term was first defined by rhetoric scholars in classical Rome times. Then it ment using and appealing to personal point of view including appeal to emotions. In contrast to it, argument could be also ad rem (to the point), or to absolute truth ad veritatem. Argument ad rem is having a purpose to support and proof the statement true with scientific methods while the goal of A.H. is often to win discussion with opponent.

There are three main types of A.H.

Ad Hominem Circumstantiae

This type of argumentum ad hominem is in pointing out circumstances that supposedly dictate a certain position to the opponent - Appeal to motive. It aims to assume the opponent’s bias and, on this basis, to doubt his arguments. This argument is also flawed, since the fact that the opponent is somehow inclined to put forward this particular argument does not make the argument itself from a logical point of view less fair.

She’s just a schoolgirl! How can she understand anything about global warming?

This overlaps with the notion of genetic error (an argument that rejects a claim based solely on its source). Although the remark about the opponent’s bias may be rational, it is, logically, not enough to refute the argument.

Tobacco company representatives who say that smoking is not harmful to your health are wrong because they are protecting their multimillion-dollar financial interests

They are not proven wrong by financial interests. If they are wrong, it is not for that reason. That statement could be refrased to avoid logical error this way:

Representatives of tobacco companies who claim that smoking is not harmful to your health are probably biased because they are protecting their multimillion-dollar financial interests. By making such statements, they may be wishful thinking or even lie.

Another example of ad hominem circumstantial:

He is physically addicted to nicotine. Of course he will defend smoking!

Could be reworded to:

He is physically addicted to nicotine. Therefore, his opinion about smoking may be biased.

Guilt by Association is a subform of ad homs circumstantial when person’s arguments are devalued because he/she is a part of a group. If argument about that made in an aggressive way there could be a Name Calling.

Ad Hominem Tu Quoque

You too - hiding problems with their own argument by pointing out that opponent himself/herself is contradicting to their own statement - accusing the party expressing the argument of inconsistency, emphasizing the inconsistency of her words or actions with her own argument. In particular, if Party A criticizes Party B’s actions, the “tu quoque” response states that Party A did the same.

It doesn’t matter what Trump does, look at what Obama did.

This line of reasoning is inherently flawed because it does not refute A’s argument; if the latter is true, then side A may have been hypocritical, but that does not make their statement any less logical from a logical point of view. Moreover, Party A may bring their personal experience to support their argument, for example,

A father may tell his son not to start smoking, as he will regret it in the future, and the son may indicate that the father smokes himself.

This does not negate the fact that the son will really regret smoking in the future.

Ad Personam

In the general case, Ad Personam consists of pointing out facts that characterize the opponent himself, but are not related to his argumentation. Its main principle is to create in the audience a general negative image of the opponent personally and, thus, create the impression that any argumentation of the opponent comes from an unworthy source. That is a direct critique of opponent, including Name Calling and Identity Politics.

He can’t be right! He is such a brainwashed simpleton!

Poisoning the well

Discrediting, appeal to ethos or smear tactics consists of preemptive sharing of adverse information (true or falce) about opponent to the audience. It’s a form of Ad Personam argument to reduce credibility of or even redicule the future opponent’s claims. Sometimes can be used with preemptive association fallacy.

Historically this fallacy took name from war operations tactics when retreating army destroyed or poisoned wells to reduce other army’s fresh water resources during the war. The Poisoning the well fallacy example would be

My opponent doesn’t have a degree, but he does look awesome, doesn’t he. Well let’s see what he has to say.

Kafka-trapping

Kafka trap is a rhetorical device, it occurs when person is accused of something but their denials are interpreted as absolute proof of their guilt.

You are a racist! No, I am not. Of course you are. You guys always deny you have this problem!”

Another example

Your refusal to agree that you are a misogynist proves you’re one of them.

Tone policing

Tone trolling, tone argument, Tone fallacy, Tone policing fallacy is an Ad Hominem Argument based on criticizing a person for expressing [excessive] emotion. Tone policing detracts from the statement by pointing out or even exaggerating (in this case it may be also Poisoning the well) the tone in which it was presented rather than the primary message.

Calm down so we can discuss this like adults.

Traitorous critic fallacy

argumentum ergo decedo Responding to criticism by attacking a arguer’s probable good relationship with other group as the main reason for their criticism rather than addressing the statement itself, and suggesting that they leave the group or stay away from the issue.

Don’t like this country? Leave it!

How to respond to Ad Hominem

If you were attacked with an Ad Hominem Argument you can respond to them by

  • responding to them directly
  • pointing out their irrelevance
  • acknowledging them and moving on
  • ignoring them

More info: