When is ad hom a fallacy?

[GreedyAlgorithm]

JetLeg brings up the question of whether or not learning an arguer was drunk at the time he made his argument should lead us to believe the argument is less likely to be true in this thread. There's something intuitively compelling about the claim that it should, and something else compelling about the claim that it's just an ad hominem.

Here is the difference:

The substance of the argument itself screens off the drunkenness of the arguer. Obviously if the argument is sound then it is sound regardless of the state of the one making the argument. If however we do not know the argument itself, then knowing that the arguer was drunk is very relevant evidence that once we know the argument, we are more likely to find it fallacious. In terms of causality, being drunk is one possible cause of making bad arguments, but is not the cause of any instantiated argument being fallacious. In the causal graph, we'd see

DRUNKENNESS ==> SPECIFIC ARGUMENT MADE ==> FALLACIOUS ARGUMENT

as one subset of the graph. Until we observe the value of SPECIFIC ARGUMENT MADE (i.e. hear the actual argument), if we observe that DRUNKENNESS is higher, we compute that FALLACIOUS ARGUMENT is higher. But if we know the actual value of SPECIFIC ARGUMENT MADE, it screens off the "probability flow" from DRUNKENNESS to FALLACIOUS, and knowing that DRUNKENNESS is higher no longer raises FALLACIOUS.

And so it is ad hom to continue to use evidence of drunkenness as evidence against the argument once you know the argument, but it is not ad hom before. This is why it's fine to decline even reading another of Ray Comfort's arguments - it's so unlikely that the argument is any good, it's a better use of your time to do other things. Did you actually read one, though, the mere fact that it is Ray Comfort's will no longer help you guess whether the argument is good or bad - you know too much now.

(or read this on argument from authority: Argument screens off authority)

 

[Arkayik]

Hic... Who cares...?

On the other hand, if they're drunk enough, will they remember the ad-hom-slur once they sober up?

Still and all, I think 42 is likely to be the best answer you'll get....

Yo, toss another cold one on the Bar-bee-que...!

 

[nzric]

Bessie Braddock: “Sir, you are drunk.”
Churchill: “Madam, you are ugly. In the morning, I shall be sober.”

 

[Cavemonster]

It is fallacious to assume that a drunk's statement is likely to be false because it's based on the flawed premise that the majority of statements made by drunks are false.
However, in some areas, this is quite reasonable. These include statements about:
1) Their current ability to drive
2) Whether or not they love you and how much
3) If it really is a good idea to call that ex at 4am
4) We're going to start a band

 

[linusrichard]

It is fallacious to assume that a drunk's statement is likely to be false because it's based on the flawed premise that the majority of statements made by drunks are false.

Yes, exactly. If you accept the premises, there's nothing wrong with the reasoning that leads to the conclusion. That is, if Jetleg tweaked his premises slightly, his argument would be valid, and not fallacious, but not at all sound.

However, in some areas, this is quite reasonable. These include statements about:
1) Their current ability to drive
2) Whether or not they love you and how much
3) If it really is a good idea to call that ex at 4am
4) We're going to start a band

Dude! A band! Yes! That's going to be so awesome! Oh, man... a band! Totally!

 

[slingblade]

I read the article.

I do not agree with:

And so it is ad hom to continue to use evidence of drunkenness as evidence against the argument once you know the argument, but it is not ad hom before.

It IS an ad hom, before, during, and after, if you are evaluating the argument in light of the condition of the arguer, and not on the argument's own strengths regardless of maker.

It is even MORE SO an ad hom before, if it prevents you even listening to the argument to evaluate it! For crying out loud, how elementary is that?

It doesn't matter who is making the argument, or what condition they are in. You must judge the argument alone, not the maker.

Whenever you focus on the maker instead of the argument, you commit an ad hominem fallacy. Period. You may be perfectly justified in doing so, but that doesn't make the fallacy disappear!

 

[linusrichard]

I think it's worth splitting the "argument" up into two parts: the premises, and the reasoning which leads to the conclusion.

If we don't know the truth of the premises, there's nothing wrong with looking at the drunkenness of the proponent as one piece of evidence that will lead us to decide whether we consider them to be true or false. I don't consider that ad hom.

If we don't know the validity of the reasoning (that is, assume the truth of the premises and ask if they lead to the conclusion), that's our own failing. We can't look to the drunkenness of the proponent as having any meaning at all. We have to judge the validity of the argument alone, as I think slingblade was saying. If we don't have the ability to judge the validity of the argument alone, our recourse is to a more capable logician, not to the PBT.

 

[slingblade]

I think it's worth splitting the "argument" up into two parts: the premises, and the reasoning which leads to the conclusion.

If we don't know the truth of the premises, there's nothing wrong with looking at the drunkenness of the proponent as one piece of evidence that will lead us to decide whether we consider them to be true or false. I don't consider that ad hom.

But that's the very definition of ad hominem!

The argument is not wrong (or right) because Bob is stinking drunk. The argument is wrong because it is wrong.

If a perfectly sober person said the same thing, would it become more true, more correct, more right than if Bob the Stinking Drunk said it?

If we don't know the validity of the reasoning (that is, assume the truth of the premises and ask if they lead to the conclusion), that's our own failing. We can't look to the drunkenness of the proponent as having any meaning at all. We have to judge the validity of the argument alone, as I think slingblade was saying. If we don't have the ability to judge the validity of the argument alone, our recourse is to a more capable logician, not to the PBT.

Exactly.

As I said, you may be emotionally justified in deciding that you don't trust or won't listen to a particular person. But none of that has anything to do with the truth or false values of his statements.

 

[GreedyAlgorithm]

It is fallacious to assume that a drunk's statement is likely to be false because it's based on the flawed premise that the majority of statements made by drunks are false.
However, in some areas, this is quite reasonable. These include statements about:
1) Their current ability to drive
2) Whether or not they love you and how much
3) If it really is a good idea to call that ex at 4am
4) We're going to start a band

There's a big difference between "is likely to be false" and "is more likely to be false". The first is talking about a total probability, and requires lots of data and evidence to bear out. The second is talking about the direction of change of probability.

 

[IMST]

You're wrong BECAUSE you're drunk: fallacious ad hom.
You're wrong AND you're drunk: not a fallacious ad hom, though there should be some other reason noted for the wrongness.

 

[phantomb]

A logical fallacy is by definition an argument that is not logically sound. A logical fallacy is still a logical fallacy even if its conclusion is correct (even if that conclusion is obvious because of another argument).

All logical fallacies are fallacious all of the time.

 

[GreedyAlgorithm]

As I said, you may be emotionally justified in deciding that you don't trust or won't listen to a particular person. But none of that has anything to do with the truth or false values of his statements.

No, you are logically justified. No weaseling out of it. The reason you're justified is because their arguments are less likely to be right, and you have better things to do. It has everything to do with the truth values of his statements - you have good reason to believe his statements will not contain much truth.

Now suppose he says "Grass is green." Does that make "Grass is green" less likely to be true? Of course not, likelihood is a function of what you know. Once you know the argument, you can evaluate it on its merits. But before you know what was said, you consider it less likely to be true.

How can it possibly be a fallacy to update your beliefs about an unknown statement based on the known speaker when it leads to truer beliefs? That's just silly.

 

[JoeTheJuggler]

You're wrong BECAUSE you're drunk: fallacious ad hom.
You're wrong AND you're drunk: not a fallacious ad hom, though there should be some other reason noted for the wrongness.

You're saying, I take it, that if the ad hominem remark is not made as part of an argument it can't be a fallacy.

On the other hand, making an ad-hom remark (even if it's simply an insult and not dressed up as an argument) in the context of a debate is still in a way fallacious. It's meant to change the discussion from a debate of ideas into an "argument" (in the non-rhetorical sense) based on emotion and conflicting wills.

So, I'd say anytime an ad hominem comment is made in the context of debate, it is fallacious. Just as it would be fallacious to try to win your debate by knocking your opponent unconscious (what I would call the "might makes right" fallacy, the "my dad can whip your dad" fallacy or the "argumentum ad majorem vim").

NB: I'm just making up this category. There is no conventionally recognized fallacy of this name that I'm aware of.

ETA: Also, if someone said, "You're wrong, and you're drunk" in the context of a debate, I'd take the implied meaning to be, "You're wrong because you're drunk."

 

[JoeTheJuggler]

A logical fallacy is by definition an argument that is not logically sound. A logical fallacy is still a logical fallacy even if its conclusion is correct (even if that conclusion is obvious because of another argument).

All logical fallacies are fallacious all of the time.

Well said.

The only way I could think of a situation where the statement, "You're drunk" is used properly during an argument would be if the proposition your opponent were arguing is, "I'm sober." Even in this bizarre situation, it would merely be an assertion of the conclusion. If used as an argument, rather than just spelling out what the two positions are, it would be begging the question.

 

[slingblade]

No, you are logically justified. No weaseling out of it. The reason you're justified is because their arguments are less likely to be right, and you have better things to do. It has everything to do with the truth values of his statements - you have good reason to believe his statements will not contain much truth.

No. That is an emotional response, not a logical one.

To say "I have decided not to waste my time listening to his arguments, because he is less likely to be right" is still an ad hominem, even if that statement is perfectly true. It is still evaluating the man, and not the argument.

Now suppose he says "Grass is green." Does that make "Grass is green" less likely to be true? Of course not, likelihood is a function of what you know. Once you know the argument, you can evaluate it on its merits. But before you know what was said, you consider it less likely to be true.

Which is why you don't dismiss the arguer. You ignore who is making the argument, and focus on the argument itself, because focusing on the person making the argument leads you to exactly this kind of fallacious reasoning.

How can it possibly be a fallacy to update your beliefs about an unknown statement based on the known speaker when it leads to truer beliefs? That's just silly.

How can you "update your beliefs" if you refuse to listen to the speaker because you don't trust him, or feel he is usually wrong? You've screwed yourself out of the chance to learn anything.

Beliefs are often wrong anyway. If you know a thing, you don't have to believe it. If you only believe it, you don't actually know and should be trying to find out.

A logical fallacy is by definition an argument that is not logically sound. A logical fallacy is still a logical fallacy even if its conclusion is correct (even if that conclusion is obvious because of another argument).

All logical fallacies are fallacious all of the time.

Exactly so. Which is why you may emotionally decide a speaker isn't trustworthy, but you are committing a logical fallacy in doing so. Until you evaluate the argument alone, you can say nothing about the argument.

 

[Piscivore]

So, I'd say anytime an ad hominem comment is made in the context of debate, it is fallacious. Just as it would be fallacious to try to win your debate by knocking your opponent unconscious (what I would call the "might makes right" fallacy, the "my dad can whip your dad" fallacy or the "argumentum ad majorem vim").

That's ad baculum, surely?

Sling, you're brilliant. Couldn't say it better myself.

 

[Skeptic Ginger]

Here's my example. Last night we were debating Creationists at our Drinking Skeptically Meetup. One of the Creationist gentleman gave his rationale that because 'he' could not explain the evidence for evolution any better than he could support the Biblical version with evidence, it was equally legit that the Bible could be correct.

Obviously the guy was poorly informed about the science involved. While I didn't use that ad hom as an open argument against him, I certainly considered it a valid criticism of his position. His ignorance was the evidence against his viewpoint.

 

[Piscivore]

Here's my example. Last night we were debating Creationists at our Drinking Skeptically Meetup. One of the Creationist gentleman gave his rationale that because 'he' could not explain the evidence for evolution any better than he could support the Biblical version with evidence, it was equally legit that the Bible could be correct.

That's argument from ignorance, already a fallacy.

Obviously the guy was poorly informed about the science involved. While I didn't use that ad hom as an open argument against him, I certainly considered it a valid criticism of his position. His ignorance was the evidence against his viewpoint.

It would be a fallacy no matter who said it, therefore it is not ad hom.

 

[jmcvann]

Did Einstein become stupid when he drank?

 

[JoeTheJuggler]

That's ad baculum, surely?

As they say, a derringer beats a royal flush. . . .

I thought I was making something up!

Sub sole nihil novi est.