Obviously it is that he has no special authority on this subject.

With 20–40 minutes of effort, someone could easily track down a large pile of peer-reviewed scholarly literature examining the contributions of Arab, Persian, Seljuk, etc. mathematicians and scientists of 800–1600 CE, and putting it in historical / scientific context.

But I doubt you really care much, or you would do the same searching for yourself. So it’s not worth the time.

Wikipedia is an aggregator not a source. It's like HN, a useful place to find links to where reputable people have said things.

No, they're probably equally lacking authority. But you cited the PhD as a better authority, when he clearly wasn't, so you sound ridiculous.

No, I don't have an opinion on your weirdly anti-Islam point, but your way of arguing it is disingenuous and unconvincing and it sounds like you have to resort to cherry-picking and touting up obscure sources to support it, so it's probably false.

I just chimed in to criticize the way you argued, in hopes that it would go away. When you said "look here's a guy with a Phd", pretending like his expertise was relevant, and then someone said that his PhD wasn't in a relevant field, you played dumb and wrote "Yes, that's correct. Not sure what your point is.", as though you couldn't perceive that citing someone as an expert when they're not makes you sound obviously uncredible.

"I would like to say "Grow up, dude", but that would be impolite." I'm not sure what would lead you to think it's somehow more polite to talk about saying something like that than actually saying, but, it's definitely not. You don't sound mature for pretending to exercise restraint.