Well, I'm going to admit something I would rather not have to admit.
Here I go:
I had to look up "ad hominem." I have heard it for years, but I thought it meant "lacking in reason," which was close.
It means, " Appealing to personal considerations rather than to logic or reason: Debaters should avoid ad hominem arguments that question their opponents' motives." -this from Dictionary.com
Phew. I feel better.