In my previous posts, What is an Argument? and Assessing Arguments, I spelt out some basics as to what an argument is and how to assess arguments. There I noted that a sound argument is one where the premises of the argument is trueand the argument is valid. It is impossible for an argument which is sound to have a false premise, this fact means that one cannot rationally reject the conclusion of an argument unless one also rejects either one of the premises or the argument’s validity.
These concepts are essential to understanding fallacies because fallacies frequently involve rejecting a person’s conclusion or their argument on grounds other than their lack of soundness. Thus, a fallacy is an error in reasoning.
Logicians have characterised and named the most common mistakes. Most have Latin names due to the fact that logic was a prerequisite to studying theology in the middle ages; Latin was the language of scholarship at that time so the classifications of fallacies were done in Latin.
The first and perhaps most infamous fallacy that I want to look at today is thead hominem fallacy. Ad hominem means “against the man.” An argument is ad hominem when the thrust of the argument is not made at against the conclusion one is denying and neither is it made against the soundness of the argument by challenging either its validity or the truth of its premises, an ad hominem argument is one where the attack on the argument is directed against the person who has offered the argument or who has asserted its conclusion.
A good example on an ad hominem occurred on MandM this week. The issue as to whether New Zealand has an established religion surfaced in a comment thread. Madeleine claimed,
“I refer you to this guest post written by lawyer David Simpkin who sets out the law showing New Zealand does have an official state religion and denomination – the Church of England (Anglican). His legal analysis is dead right. Guest Post: No Official Religion in God’s Own?.”
Here Madeleine referred the reader to an argument, made by a lawyer, which argued from certain premises to the conclusion that New Zealand has an official religion. Julian the Apostate responded to this as follows:
“Could I also note Mr Simpkin’s former role as a member of Youth for New Zealand, a front group for the Christian Heritage Party?”
Here Julian does not address the premises of Simpkin’s original argument, nor does Julian claim that the argument is invalid, instead he dismisses both the argument and its conclusion on the basis that the author of the argument, was once a member of a youth group connected with the Christian Heritage Party.
Now regardless of what one thinks of the Christian Heritage Party and regardless of whether Simpkin’s legal analysis was correct, the fact is that his past involvement in a political organisation for youth has no bearing on whether his argument is sound.
The soundness of his argument depends on whether it is possible for the premises of his argument to be true and yet the conclusion false; and, whether the premises are, in fact, true. This latter condition depends on facts about the law, facts which hold independently of whether the person offering the argument was a member of a political organisation.
One can grasp this point by doing a simple experiment. Imagine that a person who was never a member of any youth organisation connected with the Christian Heritage Party offered the same argument as Simpkin. Now, would the argument be sound? If the answer is yes then the original argument is sound. The arguments are the same, the same premises and inferences are made, so Simpkin’s former political affiliations make no difference to the argument. Likewise, if the argument was, in fact, unsound then Simpkin’s political affiliation would still be irrelevant because the argument would be unsound even if someone who is not a Christian Heritage Party affiliate made it. The political affiliation of the person making the argument makes no difference to the argument whether it is sound or unsound.
An ad hominem argument seeks to persuade by using psychological or emotional transference; the hearer is fooled into transferring their disapproval of a person onto the argument or its conclusion. The problem is that the criteria for what makes a person good is not the same as the criteria for a what makes an argument good. Failing to meet the criteria for being a good person has no bearing on whether the argument the person offers is sound or unsound.
Two Major Forms
Ad hominem fallacies come in two major forms. The first is ad hominem abusive, the second is ad hominem circumstantial.
Ad Hominem Abusive
An ad hominem abusive argument typically involves an attack on the character or integrity of the person making the argument or proposing the conclusion. He will be attacked morally or his intellectual competence is called into question or he might be smeared with a kind of guilt by association argument, whereby it is claimed his position links him in some way with the Nazis or the communists or the political right or left or the youth wing of a Christian political party, etc. Even if true, none of these attacks have any relevance to the truth or falsity of the argument or conclusion he is offering.
Suppose someone claims that the world is round. This claim will be true if the world is, in fact, round or false if it is, in fact, not round. Whether one is a Nazi, a communist, an evil rapist or a murderer does not change the shape of the earth. It is the shape of the earth alone that determines the truth or falsity of the claim that the world is round.
Ad Hominem Circumstantial
An ad hominen circumstantial is a little more subtle. This fallacy occurs when someone tries to dismiss the truth of a conclusion or rejects an argument for a conclusion on the basis of the circumstances under which the conclusion is held.
For example, a person who offers an argument for free-market capitalism, is told “you’re a wealthy business woman, it is in your interests to believe that.” This is an ad hominem circumstantial argument. Even if it is true that the person offering the argument is wealthy and even if self-interest in the real motivator for the business woman’s conclusion, the truth or falsity of her conclusion depends on whether what it affirms is, in fact, the case.
The question still arises as to whether the argument is sound. An argument does not cease to be a good argument just because someone has dubious motives for offering it or offers it under certain circumstances. It is unsound if it is invalid or if one of its premises is false. A person’s motives for adopting a conclusion or the circumstances of their supporting that conclusion tells us about the psychology of that person but it does not tell us about the truth or falsity of their argument.
But It’s True!
An ad hominem argument does not become valid just because the attack on the maker’s character is accurate. Sometimes people defend ad hominem arguments by stating “but it’s true”; they make the case that the person does possess the character flaw they are accused of holding or that the person’s belief is held under the circumstances claimed.
This response misses the point. What makes ad hominem arguments fallacious is not that the accusation made is false, it is that even if it is true it is not relevant to the truth of the conclusion under discussion or the soundness of the argument being proposed. An ad hominem argument essentially changes the subject from the claims in contention to the character of the person. However accurate or insightful this subject change may be, this new subject does not address the question that is at issue.
When Character is in Play
A final point is that there are certain circumstances in which criticising the person is not a fallacy. This is important to grasp. I noted above that what makes an ad hominen argument fallacious is that it is irrelevant to the question at hand. And ad hominem argument does not provide reasons for thinking the conclusion in question is false or that the argument is unsound. There is one situation where this is not the case. This is where the reason proposed for accepting a conclusion is the credibility of the proposer.
Celebrity endorsements are a good example of this. If a product or concept is being pitched to the public solely on the basis that the celebrity endorses it, then the credibility of the celebrity is the ground for accepting the conclusion.
New Zealand’s Prime Minister, John Key, took some of flack for his public dismissal of Whalerider actress Keisha Castle-Hughes; he said she should “stick to the acting” over her stance on climate change. At the time, Castle-Hughes was an ambassador for Greenpeace’s Sign On campaign, which saw her featured on TV, radio and print media advertisements advocating for a 40% reduction in New Zealand emissions by 2020. She had also recently visited the Cook Islands to see the impact of climate change and returned saying she wanted to meet Prime Minister Key to discuss it. Now, given that Keisha was using her Hollywood status to add authority and credibility to Greenpeace’s campaign, and she is not in fact a climatologist nor did she, in the advertisements I saw, offer any argument for her position, Key’s response “my advice to Keisha is this: stick to acting” was addressing the argument. Whatever else it may have been, it was not ad hominem.
Another example is that of the expert witness. Sometime in a court case the prosecution will call an expert witness on the stand. The jury will be asked to believe that a certain claim is true on the grounds that the witness is an expert and is telling the truth. In situations like this the prosecution has made the witness’ credibility or honesty part of the argument. The defence can legitimately attack the witness’ credibility by showing he does not have the relevant expertise or by showing his character means his testimony cannot be trusted because these approaches address the argument being made.
However, if the expert witness goes on to provide some arguments for his conclusion which move beyond merely his say so, then it is these arguments that need to be addressed; attacking his character would no longer be an attack on the argument and would not be an example of the ad hominem fallacy.
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