[Nursie]

I totally agree with his assessment of the misuse of the term ad-hominem too.

An ad-hom fallacy is "your argument is wrong because you're an immoral moron", not "your argument is wrong for these reasons, you immoral moron".

The latter is not very nice and probably shouldn't be encouraged, but it's not an ad-hominem because the insult is not part of the argument, just an unpleasant aside.

[bjhoops1]

Also, there is nothing illogical about saying "this person or source of information has a reputation for being wrong or deceitful, therefore I will not be spending my time examining their claims." This is not really an ad hominem, just saying that due to the unlikelihood of an individual having anything to contribute, you are choosing to not engage their argument. I suppose this falls under "running away from the argument".

[alexqgb]

Exactly. Which is why it would be an ad hominem (or really, ad feminum) to say "How can we possibly trust you as our CFO? You're a woman!" since there is no pertinent relationship between gender and the job's requirements. However, there's nothing illogical about saying "How can we possibly trust you as our CFO? You're a convicted embezzler!"

Indeed, if the personal considerations are this relevant, it would quite illogical not to consider them. Likewise, I someone has established a general reputation for idiocy, slop, and other crimes against lucidity, it's perfectly reasonable to flag their remarks as dubious until proven otherwise. It's actually a perfectly rational conservation of time and energy.

[JasonFruit]

Very true — it's not illogical to think that, or to use it as a reason to ignore the discussion. Responding to someone by pointing that reasoning out, however, is very seldom going to lead to productive discussion. It's usually best left unsaid.

[samatman]

Ad-hom is often invoked against arguments of the form "So-and-so advocated that position and look what happened". This is actually argument from consequence and is useful, Godwin be damned.

[jlgreco]

While we are on the topic, the whole "Godwin" shit drives me batty. Yes, I get that "You won't let me go to the dance with Timmy? You are Hitler!" is not cool, but for the most part in mature discussion that is not what is happening right before somebody starts hysterically screaming "GODWIN!"

If history is to be considered important, it is because we think we can learn from it. However our ability to do so is cut short if we reject any allusion to history in which magnitude and severity are mismatched.

For example: If you kick a small village of several dozen in Africa out of their homes to make room for a pipeline, that is not equivalent to the 'Trail of Tears', but there sure as hell are valid comparisons to be made nevertheless. However the overly enthusiastic "Godwinists" would have us believe any comparison between the two would be uncalled for.

[kmm]

It colours the argument and tries to make the other party sounds bad. Obviously this is done with the intent to "win" the argument. And thus "your argument is wrong for these reasons, you immoral moron" is a disingenuous way to reason, which comes close to a fallacy in my opinion.

Oh, and I sometimes see ad-hominem used to refer to the whole of slurs, condescension and things that are said to make me feel/look bad, regardless of whether an argument is going on.

[abraininavat]

While I agree with you for the most part, the context and nature of the debate is important. In a casual conversation that happens to be an argument, there's (usually) some semblance of a logical argument that can be teased out from a large amount of non-logical communication. In that context, picking on any of that non-logical communication and calling it a fallacy is silly.

In the context of a real debate, however, when each party has the goal of arguing a side, and an audience is there to hear and evaluate each party's words in the context of the argument, I think a phrase like "you immoral moron" is indeed to be taken as an ad-hominum. In that situation every statement is assumed to be part of your argument.

[Nursie]

It can be taken as a sign of weakness of argument, of bad technique and of uncivility, certainly. Even grounds for disqualification from a formal debate.

It's not an ad-hominem fallacy though.