From your own quote,
...directed against a person rather than the position they are maintaining.
...is often a personal attack on someone's character or motive...
So If I suggest that you're holding a particular viewpoint because you're paid by an interested party, that's an ad hominem attack.
If I suggest that your viewpoint is invalid (wholesale) because you're a moron, or some other derogatory term (like child molester), that's an ad hominem attack.
It really doesn't matter if the ad hominem attack is "true" or not. It's still an ad hominem attack if it's aimed at the person or their character or their motives (the mind reader fallacy is another common example) instead of at the LOGICAL STRUCTURE or COHERENCE of their argument.
An ad hominem attack is often in service of a rush-to-disqualify a debate partner.
Defamation and slander and libel are synonymous with ad hominem attack.
I am confused!
I needed to look it up.
ad hominem
adj. Attacking a person's character or motivations rather than a position or argument.
adj. Appealing to the emotions rather than to logic or reason.
n. To the man; to the interests or passions of the person.
how can you insult someone when it is not about wanting to change a persons way of seeing something? ether the person you are insulting or other onlookers.
Is it one of my blind spots or one of yours? I am not sure yet.
For example, if someone says "your favorite president is an idiot", it's an attempt to discredit and or disqualify anything and everything they say (and strongly implies that you're also an idiot for choosing such a buffoon as your favorite president, the guilt-by-association fallacy).
It isn't specifically aimed at undermining a particular "argument" or "position" they might espouse, it is a general dismissal of EVERYTHING they've done and or might do in the future.
Saying, "your favorite president is an idiot" is an ad hominem attack (both a direct and indirect attack).
It's also a broad-brush fallacy.
It's also a bald-assertion.
It's also an appeal-to-ignorance.
(1) Please provide an example of an ad hominem attack that is NOT an insult.
(2) Please provide an example of an insult that is NOT an ad hominem attack.
Citation please.
So, if someone says, "I think you're a lying dog-faced pony-soldier", that's NOT an ad hominem attack in your opinion because it's "TRUE" (that person is presumably sincere)??
The key problem here is that character is QUALITATIVE (GNOSIS).
The other key problem here is that motives are QUALITATIVE (GNOSIS).
And you seem to be glossing-over the point that even your source specifies "in SOme instances" (probably when the question tautologically involves questions of "character" and or "motive", of course under those conditions "character" and or "motive" would necessarily be relevant). HOWever, "character" and "motive" are both beyond our epistemological limits (un-quantifiable, self-reported, implicit, subconscious).
And your bald assertion that an ad hominem attack is not fallacious if it's "true" is not supported by any of your quoted sources.
The key problem here is that character is QUALITATIVE
Because there is no way to QUANTIFY "character".
And without QUANTIFICATION there is no way to verify a claim's "TRUTH-VALUE".
Your quote "explains" no such thing.
It simply asserts that in SOME cases, presumably if the subject at hand is specifically about a person's history and or personal choices, data relevant to such an inquiry CANNOT be considered off-limits.
HOweVer, I can't imagine a case where a person's history and or personal choices would be a subject of scrutiny wholly divorced from any explicit or implicit attack or endorsement of their abilities and or ideas WHOLESALE.
A "positive" ad hominem is just as fallacious as a "negative" ad hominem.
You shouldn't believe someone just because they're a doctor.
You shouldn't disbelieve someone just because they're a commie.