I had a disagreement with my boss. He insisted that we should move forward on a project his way instead of mine. To make his case, he began criticizing me.
When I called him out for a personal attack instead of my position, he was tongue-tied. He didn’t even realize his argument was commiting a common fallacy: the ad hominem.
What Is an Ad Hominem Fallacy?
Ad hominem arguments look to falsify a claim by attacking the person who’s making the claim. Since claims are true or false regardless of who makes them, the person who is making the claim is irrelevant to evaluating the claim’s truth or falsity.
For example, if Hitler claims that 2 + 2 = 4, that doesn’t automatically make the claim false. Hitler is a bad person, but that doesn’t mean that everything he says is false. Dismissing a claim simply because a bad person says it is an example of Ad hominem.
When people commit an ad hominem fallacy, they are mistaking criticism of a person with criticism of a claim or an argument. The Latin term ‘Ad hominem’ means “to the person.” When people commit an ad hominem fallacy, they’re attacking the arguer in an effort to falsify the arguer’s claim. It’s a fallacy because attacking the person can’t succeed in falsifying the claim. The truth or falsity of the claim is completely independent of the person who makes it.
Some synonyms for “Ad hominem” include, “Appeal to the person,” “Personal abuse,” “Verbal abuse fallacy,” “Name-calling,” “Ad hominem attack,” and “Argumentum ad hominem.”
Here’s what ad hominem looks like:
Alex: “We should have free college for all, so more people can get a college degree.”
Jen: “No, college shouldn’t be free. You’re just a hippie.”
This is a logical fallacy because attacking the person with abusive remarks or name-calling does not prove the claim to be false. Even if Alex is a hippie, that doesn’t give us any reason to think that what Alex says is false. Alex could just as easily say that 2 + 2 = 4. Would Jen reject that claim as well?
An argument is bad because of its logic, not because of the person who makes it.
Ad Hominem as the Mirror Image of Appeal to Authority
Ad hominem is often a mirror image of appeal to authority. In ad hominem, someone appeals to negative characteristics of a person to reject a claim, and in an appeal to authority, someone appeals to the positive characteristics of a person to accept a claim. Both appeals are fallacious because the characteristics of the person are irrelevant to whether the person’s claim is true.
Sam, “There is an afterlife.”
Sam is a devil.
So, there is no afterlife.
Appeal to Authority
Sam, “There is an afterlife.”
Sam is a saint.
So, there is an afterlife.
Contrast the earlier Hitler example with another: If Mother Teresa claims that you should give money to the poor, that doesn’t automatically make the claim true.
People with negative characteristics can still be right, and people with positive characteristics can still be wrong, so discussing personal characteristics instead of the claim itself is a fallacy.
Some common traits that people think are either negative or positive are based on people’s social, physical, personality or characteristic traits. Examples include being rude or polite, being obese or thin, being a man or a woman, being loud or quiet, being conservative or liberal, being rich or poor, being a KKK member or an ACLU donor. All and all, it could be any characteristic of a person that factors into an ad hominem.
Ad hominem is so common because evaluating people is so familiar to us. It’s one of the first things we learn to do in childhood. Because that way of evaluating things is so familiar, people tend to default to it even when it’s irrelevant. This results in ad hominem being one of the most common fallacies—like tu quoque or straw man.
Here are some examples of personal attack, aka ad hominem:
Anderson Cooper said, “We should eliminate the death penalty because it is inhuman,” but Cooper is a left-leaning political head, so his claim must be false.
Explanation: It doesn’t matter what political party Anderson Cooper endorses; we are evaluating his claim about the death penalty, so we need to remove Cooper from the equation to avoid an ad hominem fallacy.
James said, “College is a waste of time.” Since James didn’t go to college, he has to be wrong.
Explanation: Again, we’ll need to look at James’s claim rather than his background. He could very well be wrong, but we can’t dismiss his claim based on whether or not he went to college.
Trump said, “The USA is the best place to start a business because the tax rates are so low for small businesses.” Since Trump is a pig in human clothing, this claim is false.
Explanation: You can’t reject an argument simply because it comes from someone you dislike. The argument itself needs to be evaluated before accepting, rejecting, or withholding judgment about the conclusion.
Rob says that we shouldn’t have affirmative action. But Rob isn’t a minority, so we should reject that claim.
Explanation: Again, we will need to look at Rob’s claim rather than his background. He could very well be wrong, but we can’t dismiss what he says simply because of his genetics.
Sally says we should help the poor, but she grew up in a rich family, so she doesn’t know what she’s talking about.
Explanation: We will need to evaluate Sally’s claim rather than her upbringing. She could very well be wrong, but we can’t dismiss what she says simply because of her family’s economic circumstances.
How to Disarm Personal Attack
Most of the time, people resort to ad hominem attacks because evaluating people is something they learned from an early age. It takes skills to argue against a good argument or claim, and most people aren’t skilled at doing it, so they fall back on something that’s more familiar, easy, and comfortable: evaluating people instead of arguments and claims.
If someone attacks you and not your claim, then point out that it is the claim that needs to be evaluated not the person making it. By focusing attention back on the claim, you’re bringing the fallacy to light and bringing the discussion to a more productive place.
Also, politicians are notorious for using dirty tricks to attempt character assassination. Next time you hear them talk about their opponents, be on the lookout for personal attacks that altogether avoid dealing with the opponent’s argument.
Free Thinker Approach to Ad Hominem
Free thinkers are interested in knowing and understanding what’s true, and they are interested in the evidence, not the source. In every case, the claim needs to be evaluated, not the person who makes it.
In general, you need to completely remove the person who’s making the claim from your evaluation of the claim. This is the only way to avoid an ad hominem fallacy and ensure that you’re genuinely focused on knowing and understanding what’s true.