Ad Hominem
You have doubtless heard ad hominem attacks before – though you may not have known they were an informal fallacy. Read this section on the ad hominem fallacy for a definition and examples of these attacks. After reading, you should be able to identify ad hominem attacks when you encounter them.
"Ad hominem" is a Latin phrase that can be translated into English as the phrase,
"against the man". In an ad hominem fallacy, instead of responding to (or
attacking) the argument a person has made, one attacks the person him or
herself. In short, one attacks the person making the argument rather than the
argument itself. Here is an anecdote that reveals an ad hominem fallacy (and
that has actually occurred in my ethics class before).
A philosopher named Peter Singer had made an argument that it is
morally wrong to spend money on luxuries for oneself rather than give all
of your money that you don't strictly need away to charity. The argument
is actually an argument from analogy (whose details I discussed in section
3.3), but the essence of the argument is that there are every day in this
world children who die from preventable deaths, and there are charities who could save the lives of these children if they are funded by
individuals from wealthy countries like our own. Since there are things
that we all regularly buy that we don't need (e.g., Starbuck's lattes, beer,
movie tickets, or extra clothes or shoes we don't really need), if we
continue to purchase those things rather than using that money to save
the lives of children, then we are essentially contributing to the deaths of
those children if we choose to continue to live our lifestyle of buying
things we don't need, rather than donating the money to a charity that
will save lives of children in need. In response to Singer's argument, one
student in the class asked: "Does Peter Singer give his money to charity?
Does he do what he says we are all morally required to do?"
The implication of this student's question (which I confirmed by following up
with her) was that if Peter Singer himself doesn't donate all his extra money to
charities, then his argument isn't any good and can be dismissed. But that
would be to commit an ad hominem fallacy. Instead of responding to the
argument that Singer had made, this student attacked Singer himself. That is,
they wanted to know how Singer lived and whether he was a hypocrite or not.
Was he the kind of person who would tell us all that we had to live a certain way
but fail to live that way himself? But all of this is irrelevant to assessing Singer's
argument. Suppose that Singer didn't donate his excess money to charity and
instead spent it on luxurious things for himself. Still, the argument that Singer
has given can be assessed on its own merits. Even if it were true that Peter
Singer was a total hypocrite, his argument may nevertheless be rationally
compelling. And it is the quality of the argument that we are interested in, not
Peter Singer's personal life and whether or not he is hypocritical. Whether
Singer is or isn't a hypocrite, is irrelevant to whether the argument he has put
forward is strong or weak, valid or invalid. The argument stands on its own and
it is that argument rather than Peter Singer himself that we need to assess.
Nonetheless, there is something psychologically compelling about the question:
Does Peter Singer practice what he preaches? I think what makes this question
seem compelling is that humans are very interested in finding "cheaters" or
hypocrites - those who say one thing and then do another. Evolutionarily, our
concern with cheaters makes sense because cheaters can't be trusted and it is
essential for us (as a group) to be able to pick out those who can't be trusted.
That said, whether or not a person giving an argument is a hypocrite is irrelevant
to whether that person's argument is good or bad. So there may be
psychological reasons why humans are prone to find certain kinds of ad hominem fallacies psychologically compelling, even though ad hominem
fallacies are not rationally compelling.
Not every instance in which someone attacks a person's character is an ad
hominem fallacy. Suppose a witness is on the stand testifying against a
defendant in a court of law. When the witness is cross examined by the defense
lawyer, the defense lawyer tries to go for the witness's credibility, perhaps by
digging up things about the witness's past. For example, the defense lawyer
may find out that the witness cheated on her taxes five years ago or that the
witness failed to pay her parking tickets. The reason this isn't an ad hominem
fallacy is that in this case the lawyer is trying to establish whether what the
witness is saying is true or false and in order to determine that we have to know
whether the witness is trustworthy. These facts about the witness's past may be
relevant to determining whether we can trust the witness's word. In this case,
the witness is making claims that are either true or false rather than giving an
argument. In contrast, when we are assessing someone's argument, the
argument stands on its own in a way the witness's testimony doesn't. In
assessing an argument, we want to know whether the argument is strong or
weak and we can evaluate the argument using the logical techniques surveyed
in this text. In contrast, when a witness is giving testimony, they aren't trying to
argue anything. Rather, they are simply making a claim about what did or didn't
happen. So although it may seem that a lawyer is committing an ad hominem
fallacy in bringing up things about the witness's past, these things are actually
relevant to establishing the witness's credibility. In contrast, when considering
an argument that has been given, we don't have to establish the arguer's
credibility because we can assess the argument they have given on its own
merits. The arguer's personal life is irrelevant.
Source: Matthew J. Van Cleave
This work is licensed under a Creative Commons Attribution 4.0 License.