5.5.1 Fallacies of Relevance

In fallacies of relevance, the arguer presents evidence that is not relevant for logically establishing their conclusion. The reason why fallacies of relevance stick around is because the evidence seems relevant—meaning it feels relevant. Fallacies of relevance prey on our likes and dislikes. Indeed, the very first fallacy of relevance is called “appeal to emotion.”

Appeal to Emotion

Emotional appeals can target any number of emotions—from fear to pity and from love and compassion to hate and aversion. For the most part, appeals to emotion of any kind are not relevant for establishing the conclusion. Here’s an example:

I know the allegations against the governor seem serious. However, he’s in his 80s now, and he fought for our country in the Korean War, earning a Purple Heart. We don’t want to put an elderly veteran through the ordeal of a trial. I urge you to drop the charges.

In this example, the arguer appeals to our feelings of pity and compassion and to our positive feelings about the governor. We might admire the governor for his military service and feel sympathy for his advanced age. But are our feelings relevant in making the decision about whether to drop criminal charges? Notice that the arguer says nothing about the content of the charges or about whether the governor is innocent or guilty. Indeed, the arguer says absolutely nothing that’s relevant to the conclusion. How we feel about somebody is not a logical determinant to use in judging guilt or innocence.

Ad Hominem Attacks

The ad hominem attack is most often committed by a person who is arguing against some other person’s position. “Ad hominem” in Latin means “toward the man.” It is so named because when someone commits this fallacy, the reasons they give for their conclusion concern the characteristics of the person they are arguing against rather than that person’s position. For example, the arguer may verbally attack the person by making fun of their appearance, intelligence, or character; they can highlight something about the person’s circumstances like their job or past; or they can insinuate that the person is a hypocrite.

You may wonder why such arguments are effective, and one reason is sloppy associative reasoning, wherein we problematically assume that characteristics held by an arguer will be transferred to their argument. Another related reason is that too often we allow ourselves to be ruled by emotion rather than reason. If we are made to feel negatively toward a person, those feelings can cloud assessment of their arguments. Consider the following example:

My fellow councilwoman has argued for the city solar project. But what she failed to mention was that she has been arrested twice—once for protesting during the Vietnam War and another time for protesting the 2003 invasion of Iraq. She’s a traitor and a liar. Any project she espouses is bad for the city.

This is clearly an ad hominem attack. The arguer wants to undermine the councilwoman’s position by making us feel negatively toward her. The fact that a person engaged in protests in the past has no bearing on their arguments for an energy project. Furthermore, the arguer goes on to call the councilwoman a traitor and a liar and offers no evidence. Attaching negative labels to people is one way to manipulate an audience’s emotions.

There are other types of ad hominem attacks, and the most successful is probably the one called tu quoque, which means “you too” in Latin. When someone commits a tu quoque ad hominem fallacy, they attempt to undermine a person’s argument by pointing to real or perceived hypocrisy on the part of the person. They assert or imply that their opponent, in the past or currently, has done or said things that are inconsistent with their current argument. Often tu quoque is used as a defensive maneuver. Take the example of a teenager whose father just caught her smoking cigarettes and reprimanded her. If she knows that her father smoked when he was her age, her defensive response will be “You did it too!” She is likely to think he is a hypocrite who should not be heeded. However, the daughter reasons poorly. First, a person’s actions have no bearing on the strength of their arguments or the truth of their claims (unless, of course, the person’s arguments are about their own actions). That her father smoked in the past (or smokes currently) has no bearing on whether smoking is in fact dangerous. Smoking does not suddenly cease to be dangerous because the person explaining the dangers of smoking is a smoker.

You might think, however, that we should not trust the reasoning of hypocrites because hypocrisy is a sign of untrustworthiness, and untrustworthy people often say false things. But remember that there is a difference between a truth analysis and a logical analysis. If smoking has bad consequences on health and development, then that counts as a good reason for the father to not allow his daughter to smoke. But interestingly, some cases of perceived hypocrisy make the supposed hypocrite more trustworthy rather than less. And the smoking example is one such case. Of all the people who might be able to speak of the dangers of picking up a smoking habit at a young age, the father, who became addicted to cigarettes in his teenage years, is a good source. He speaks from experience, which is a second reason the daughter reasons incorrectly in thinking she should not listen to him because he was or is a smoker.

Let’s take a different scenario. Suppose a married person argues that it is immoral to cheat on one’s spouse, but you know he has a mistress. As much as you may hate it, his status as a cheater is not relevant to assessing his argument. You might infer from his hypocrisy that he does not believe his own arguments or perhaps that he suffers guilt about his actions but cannot control his cheating behavior. Nonetheless, whatever the cheater believes or feels is simply not relevant to determining whether his argument is good. To think that whether a person believes an argument affects the truth of that argument is tantamount to thinking that if you believe X, the belief itself is more likely to make X happen or make X true. But such an approach is magical thinking, not logic or reason.