Yes, because I'd expect HN readers to understand an ad hominem when they see one.

I could be living in a ditch down by the river, or I could be the leading researcher into how people learn calculus and it wouldn't make a difference with regard to my argument (though, practically speaking if I were the lead researcher on how people learn calculus, I'd be more likely to back my argument up with objective research, and that would strengthen my argument).

Ad hominem occurs when you use someone's reputation in another area to discredit someone on an unrelated matter. For example, you're the worst golfer on the planet so I say you don't know how to cook. Golf expertise has no bearing on your cooking skills. But if you consistently burned toast or you mainly use your oven to heat up frozen pizza, I'm going to take anything you say about baking a cake with a giant grain of salt.

No, ad hominem occurs when you use who a person is rather than their argument to claim they are incorrect. Here's a definition from Google:

> (of an argument or reaction) directed against a person rather than the position they are maintaining.

Nothing about a reputation or using it to discredit them.

For example, I'm not a calculus teacher, therefore I couldn't possibly form a valid argument about how teaching works. That would be an ad hominem, because it focuses on who I am (not a teacher), rather than what I've said (the teacher I was replying to hasn't eliminated any variables at all before drawing their conclusion). (It's also nonsensical, considering how many other things people teach, and how small a percentage of all teachers calculus teaching ends up being, and how unrelated-to-the-science-of-education calculus is).

It's actually funny, because the example you've given isn't an ad hominem, since you have evidence to support the idea that I can't cook (the burnt toast). You're equating an absence of information about me with specific data, which is different.

You don’t know what an ad hominem is. You are incorrectly applying the definition. It is not an argumentative fallacy to ask the basis by which a person’s assertions have been formed. You’ve made lots of claims about teaching but clearly you have no experience to back it up and (this is important) you have not provided any citations to back up your assertions.

People have to make judgments with imperfect knowledge. It’s reasonable to discount the unsubstantiated opinions of someone with no experience with the topic at hand.

It should at least be interesting to you that it was obvious from your comments that you don’t have experience teaching mathematics in the classroom. Why was that so obvious to those of us with that experience? The previous question is rhetorical.

I didn't say it was an argumentative fallacy to ask the basis by which a person's assertions have been formed, I said it was a fallacy to say a person's assertions are wrong because of some aspect of themselves, which is what's taken place here by insisting I must be a calculus teacher in order to challenge your assertion that IQ is the primary source of the problems your students have with learning in your classrooms.

What is interesting to me is the fact that you retreated to this ad hominem the moment you were challenged, because it tells me you don't have any real explanation for how you eliminated other possible causes for your students sometimes performing poorly.

You'd prefer to live in a world where your experience has meaning than to live in a world where your experience is not valuable when faced with this question, which is completely human of you, but ultimately not useful in this discussion, due to its anecdotal and un-rigorously collected nature.

I can't stop you from throwing this New Yorker article, and the other works of Dr. Harden, in the face of your colleagues, but I can hopefully dissuade others from making the same logical mistakes you're making. I believe I've succeeded at that, by clearly highlighting the carelessness of what you've said here.

Ultimately, what I find most fascinating is, in real time, you've demonstrated how right Dr. Turkheimer ultimately is and how dangerous this research can be when put in the hands of folks who don't understand its delicacy or even the basic facts surrounding these arguments.

I'm grateful for your engagement with me, it's been helpful to work through this with someone like you, but I'll commit to the thing you tried and failed to do; I'm no longer going to reply to your comments in this thread. You're clearly (and I mean clearly) wrapped up in a need to think of some of your students as too dumb to learn calculus, and there's literally nothing I or anyone else here can say that would convince you otherwise, and at this point I've done my part in preventing others from thinking that your insight is useful or helpful in this conversation.

Have a great rest of your evening!

I committed to not responding to you in a different thread. I did not commit to not responding to you in all threads. The teacher in me forced me to try to explain to you why your use of ad hominem was incorrect. My previous response had nothing to do with what was being discussed as such. Your conclusions have not been logically valid.

Here’s an example:

… I must be a calculus teacher in order to challenge your assertion that IQ is the primary source of the problems your students have with learning in your classrooms..

No one has said any of these things and no one has implied any of these things. I never said or implied that IQ is the primary source of anything. No one believes that you must be a teacher of calculus to be right. What people have wondered is if you are a teacher because some of your statements seem to the the type of statements only a non teacher would make.

Oh, well, if you're a leading researcher in math pedagogy, you should just say so and save time. Such credibility would offer serious firepower to the debate.

I don't think it would or at least should.