When is ad hominem legitimate

How to Disagree (Paul Graham)

Translation of an article by Paul Graham dated December 19, 2008.

The web turns written documents into conversation. Twenty years ago authors wrote and readers read. The Web allows readers to reply, which they are increasingly making use of - in the form of comments, on forums and on their own blogs.

Many who respond and reply to a post disagree with it. That is to be expected. Agreeing tends to motivate people less than disagreement. And when you agree with something, there is less to say. One can elaborate on something the author wrote, but he has probably already considered the most interesting implications. If you disagree, you are entering territory that the author may not have explored.

The result is that contradictions are much more frequent, especially when the number of words is used. That doesn't mean people are angrier. The structural change in the way we communicate is sufficient for evidence. But even if it is not anger that causes the rise in disagreement, there is still a risk that it will make people more angry. Especially online, where it's easy to say things that you would never say face to face.

As we all contradict more and more frequently, we should be careful to do so appropriately. What does it mean to contradict appropriately? Most readers will know the difference between verbal abuse and carefully argued refutation, but I think it helps to identify the intermediate stages. So there follows an effort to create a "hierarchy of contradictions".


  1. WH0: abuse
  2. WH1: Ad Hominem
  3. WH2: Criticism of the tone of voice
  4. WH3: contradiction
  5. WH4: Counter-argument
  6. WH5: Refutation
  7. WH6: Refute the main point
  8. What this means

WH0: abuse

This corresponds to the lowest level of contradiction, and perhaps also the most widespread. We've all seen comments like:

You Faggot!!!!!!!!!!

It is important to note, however, that the more eloquent verbal abuse is no more weighty, so it is no better. A comment like

The author is a self-important dilettante.

isn't really anything other than "you fagot".

WH1: Ad Hominem

An "ad hominem" attack ("directed at humans") is not quite as weak as mere insulting. It can actually have some weight. For example, if a MP wrote in an article that MPs' salaries should be increased, one might reply:

Of course he says so. He's a MP, after all.

While this does not refute the writer's argument, the statement may at least be relevant to the case. Still, this is quite a weak form of contradiction. If there is something wrong with the MP's argument, it should be said what it is; what difference does it make that he is a member of parliament if there is nothing wrong with the statement?

To say that the author lacks the competence to write on a particular subject is a special type of "ad hominem" attack - and one that is particularly useless because good ideas often come from outsiders. The question is whether the author is right or not. If a lack of expertise is responsible for making mistakes, point them out. If it doesn't, there is no problem.

WH2: Criticism of the tone of voice

At the next level, we begin to see responses to the spelling, not the author himself. The lowest form of these responses is disapproval of the author's tone, for example:

I can't believe the author would so haughtily dismiss intelligent design.

While this is better than attacking the author, such comments are still a weak form of contradiction. It is much more important whether the author is wrong or correct, not what his tone is. And this is all the more true since sound is difficult to judge. Someone who is complex about certain issues may feel attacked by a tone that is neutral to others.

So if the worst thing you can say about anything is tone, don't say much. Is the author sloppy, but right? Better that than serious and wrong. And if the author is wrong elsewhere, tell me where.

WH3: contradiction

At this level we finally get responses to what was said, not the how or who. The lowest form of answering an argument is to simply take the opposite position with little or no supporting evidence.

This practice is often combined with WH2 statements, as in:

I can't believe the author would so haughtily dismiss intelligent design. Smart design corresponds to a legitimate, scientific theory.

Contradiction can sometimes carry weight. Sometimes just seeing the opposing case explicitly stated is enough to see that it is legitimate. However, evidence usually helps.

WH4: Counter-argument

At level 4 we reach the first type of convincing contradiction, the counter-argument. Up to this point, criticism can usually be ignored as it proves nothing. Counter-arguments can prove something. The problem is that it's hard to tell what.

A counter-argument means contradiction plus reason or proof. When aimed directly at the original argument, it can be convincing. Unfortunately, it is common for counter-arguments to aim at something slightly different. In most cases, two passionately arguing people are actually arguing over two different things. Sometimes they are even of the same opinion, but so preoccupied with their bickering that they do not even notice it.

There can be a valid reason to argue against something that is slightly different from what the author said - if you feel like it doesn't get the point. If you do, however, make a specific statement that you will.

WH5: Refutation

The most convincing type of contradiction is refutation. It is also the rarest because it means the most work. In fact, the hierarchy of contradiction forms a pyramid in the sense that the higher you go, the fewer examples you will find.

To disprove someone, you probably have to quote them. You need to find the crucial evidence, somewhere that says what you think is wrong, and then explain why it is wrong. If you can't find a quote to disagree, you may be arguing with a "straw man."

While refutation usually involves quoting, quoting does not necessarily imply refutation. Some authors cite excerpts from things that they contradict in order to first give the appearance of a legitimate refutation, only to come up with an answer at the level of WH3 or even WH0.

WH6: Refute the main point

The pull of a rebuttal depends on what you are refuting. The most powerful form of contradiction is to refute the main point.

Even at the WH5 level, we sometimes see willful dishonesty when someone takes up and refutes minor points in an argument. The manner in which this is done sometimes corresponds to a more sophisticated form of "ad hominem" attack than actual refutation, such as correcting spelling or poking around on minor mistakes in names or numbers. As long as the opposing argument doesn't depend on it, the sole purpose of correcting such errors is to discredit the opposing party.

To really refute something, one has to deal with the main points, or at least one of them. And that means that you are explicitly committed to what the main point is. A really effective refutation would look like this:

The author's point seems to be. He says:

But this is wrong for the following reasons

The quotation that you cite as incorrect does not have to correspond to the actual statement of the author. It is enough to refute something on which the statement in question is based.

What this means

We now have a method of classifying contradiction. What does that bring us? Something that gives us this hierarchy Not there is to determine a winner. WH levels only describe the type of statement, not whether it is correct. A WH6 answer can still be completely wrong.

While WH levels do not determine a lower limit for the persuasiveness of an answer, they do set an upper limit. A WH6 answer may not necessarily be convincing, but a WH2 or lower comment is never convincing.

The most obvious benefit of classifying forms of contradiction is that it helps people better judge what they are reading. In particular, it helps them to see through intellectually unfair arguments. An eloquent speaker or writer can give the impression of overcoming an opponent simply by using powerful words. In fact, this corresponds to a quality that defines a demagogue. By giving names to the different types of contradiction, we are giving critical readers a needle to pop such balloons.

Such labels can also help authors. Intellectual dishonesty is mostly unintentional. Someone who argues against the tone of something they disagree with may believe that they are really saying something. "Zooming out" and looking at your own position on the contradiction ladder may inspire you to move up towards a counter-argument or refutation.

However, the biggest benefit of disagreeing well is not only that it makes conversations better, but it also makes the people involved in it happier. When you study conversations, you notice that there is a lot more wickedness in WH1 below than in WH6 above. You don't have to be mean if you want to make a real statement. In fact, you don't want to. When you really have something to say, wickedness just gets in the way.

If it makes people less malicious to move up the objection ladder, it will make most of them happier. Most people don't like to be malicious; they do this because there is no other way of knowing what to do.