Students often ask me to recommend a good introduction to philosophy, and now the question can be answered more easily than in years past. Michael Huemer’s Knowledge, Value, and Reality, published last April, contains a profusion of arguments on important topics and is written in a conversational style that is easy to follow, and is often very funny as well. Huemer is especially good at coming up with objections and counters to these objections, in a way that shows how contemporary analytic philosophers work.
In what follows, I’m going to discuss a few of his points about fallacies in reasoning. He notes that some philosophers misuse “begging the question.” “The philosopher starts out with the idea that an argument begs the question (and therefore is fallacious) when someone who rejects the conclusion wouldn’t (or shouldn’t, or couldn’t reasonably be expected to) accept all the premises. That italicized phrase is treated as something like a definition of the fallacy.” (p.70, emphasis in original)
Consider the following argument:
It’s wrong for any person to initiate force against other peoplePeople in the government are peopleIt’s wrong for people in the government to initiate force against other people.
Suppose a statist looks at this argument and says, “I think that people in the government should be able to initiate force against others. I reject the conclusion, so something is wrong with this argument.” (It is likely that he will reject the first premise: denying the second doesn’t seem promising.) Are those who use the argument guilty of begging the question against statists?
No, they aren’t. Huemer points out that the definition given of “begging the question” is wrong: “People who fall for this mistake often fail to notice that it represents a rejection of all valid deductive reasoning. In a valid deductive argument, by definition, if all the premises are true, the conclusion must be true. That is logically equivalent to the following: If the conclusion is false, then one of the premises must be false. So if you start by assuming the conclusion is false, and the argument was valid, you can always deduce that (at least) one of the premises is false.” (pp.70-71, emphasis in original)
I would add to what Huemer says that some followers of Karl Popper do hold the view, which Huemer rightly takes to be absurd, that all deductive arguments beg the question. But they mean by this no more than that the premises in a valid argument entail the conclusion. They do not mean that all deductive arguments are fallacious. But why, then, do they use a phrase, “begs the question,” that in common use suggests something is amiss?
Huemer suggests that a better definition of “begging the question” is: “You beg the question when the justification of one of the premises depends upon the justification of the conclusion.” (p.71, emphasis in original) An example would be:
Statements about political questions made by A are always wrong
A said “p” about a political question
“P” is wrong.
Here, unless some general characteristic about A’s making a statement about a political question guarantees its falsity, the truth of the first premise depends on looking at all of A’s political statements and seeing they are all wrong. But “p” is one of these statements, so the justification for the first premise depends on the justification of the conclusion.
This is an example of what Huemer calls a “false fallacy,” in which a common understanding of a fallacy is wrong and leads people wrongly to dismiss good reasoning. I’d like to turn to another example of this phenomenon, although Huemer just includes it on his list of fallacies and not on the “false fallacy” list. (My comments on this fallacy are, however, related to what he says about ad hominem arguments.) This fallacy is “poisoning the well,” about which Huemer says, “This is a rhetorical strategy of trying to undermine an interlocutor by warning the audience that he can’t be trusted for some reason. This is supposed to make it impossible for the interlocutor to defend himself, since the audience won’t listen to what he might say in his own defense.”
For poisoning the well to have a chance to work, it must be the case that accepting what the person says involves trust. If, for example, a politician says that he won’t raise taxes and you tell people he is a habitual liar, then you meet a necessary condition for poisoning the well. (That isn’t to say that you have poisoned the well: if he really is a liar, are you guilty of a fallacy in pointing this out?) But sometimes, this condition is ignored, and if you make any unfavorable comment on someone, you are accused of poisoning the well against them. In one such case, a self-styled philosopher suggested that because I had said in a book review that he made mistakes, I was guilty of this fallacy. If this wrong account of poisoning the well were accepted, it would altogether destroy critical discourse. I won’t mention the person in question; suffice it to say that he has not only kissed the Blarney Stone but has had a prolonged romantic involvement with it.
Huemer also challenges misuse of the statement “correlation doesn’t imply causation.” He says, “The saying means that just because A and B go together regularly does not mean that one causes the other. Students learn the slogan in college and think it’s sophisticated, but it’s kind of simplistic. Granted, if there is a reliable correlation between A and B, that does not guarantee that there is a causal connection. It could just be a coincidence. But if the correlation is well established, it becomes vanishingly small that it’s just a coincidence. There will be some causal explanation. Maybe A causes B, or B causes A, or some third factor, C, causes both A and B.” (p.71-72, emphasis in original)
The author says that there are errors not on the traditional list of fallacies that people need to take into account, and I shall close with one example. He points out that people often assume things that seem obvious to them but are not based on evidence and are in fact false. One example of this is especially interesting. “[S]uppose you hear a statistic saying that most family members are killed by a family member or someone they knew. You naturally assume that most murders result from domestic disagreements, and that the murders are committed by ordinary people who lost control during an argument with a family member, or something like that. In fact, it turns out that almost everyone who commits a murder had a prior criminal record. Also, the vast majority of the victims are also criminals.” (pp 72-73, emphasis in original)
Everyone interested in reasoning well should read Huemer’s outstanding book. Had it been available years ago, I might have been able to avoid fallacies in my own reasoning, possibly including those committed in criticizing some of Huemer’s arguments.