[ontoillogical]

1) When I was learning what "5 times 3" was I don't think I could even pronounce "commutative," let alone understand what it meant. I did know that 3 x 5 was the same as 5 x 3, but 5 / 3 was not 3 / 5 though!

2) Javascript's equality operators can confuse even longtime practitioners and bringing them up muddles the point.

I think the author is trying to say that 5 x 3, 3 x 5, and 30 / 2 are equivalent but not equal because they represent different operations, which he is somehow equating to types in computer science? This is nonsense, all three expressions are obviously the same type, and they are referentially transparent mathematical expressions, so they would be equal not just equivalent.

3) Setting students up for matrix multiplication? Really?