Um, no. An ad hominem argument would be if I were attacking 551199's character which I'm not. Instead, 551199 cited D'Souza as a reliable source and I attacked D'Souza's character. See the difference? Good.

I am however, impeaching D'Souza's credibility as a source.

..based on political views you find odious, rather than directly attacking what you think is right or wrong about the particular (unrelated) statement in question. That is an ad hominem argument.

> ..based on political views you find odious

Well, I didn't know that a felony conviction or cheating on your wife were political views. However, given the current President, perhaps you're right.

Ad hominems are not always fallacious:

https://en.wikipedia.org/wiki/Ad_hominem#Non-fallacious_reas...

Specifically, pointing out the obviously biased nature of a source calls to question the credibility of said source, even before we get to addressing the argument itself.

I agree. Attack the argument not the arguer.

Again, the arguer was+is 551199 and I'm not attacking him. However, he did trot out the odious Dinesh D'Souza and I felt it necessary to put that cretin into his proper context. So I'm not attacking the arguer; I'm attacking his alternate facts.

No, he got paid to speak about the importance of family and the evils of gay marriage.

And this has what to do with the correctness or incorrectness of his analysis?

He makes a living being a partisan Republican. That means he can't be impartial.

Being able to practice what one preaches is a useful heuristic on how authentically one holds that position.

..which is still a poor proxy for correctness or incorrectness.

k, but the people who fired him for it disagree