-
I know nothing about it other that teachers are taught that there are 8 or 9 different forms of intelligence (depending who's training you). No idea at all if it's contentious.or simplistic.
It they're taught it the way you describe, then it certainly is. It's a way of categorising children and treating them according to those categories, rather than categorising behaviours and seeing that a child might have the potential to learn others. "Hey, kids, you get to play at Myer's Briggs just like the adults."
I think that's both a simplistic description of things and difficult to prove, without some means of being able to read people's minds. We can observe and measure the ways people behave but we aren't currently capable of directly observing how they think. Safer to say that there are different areas in which people could potentially apply their intelligence and most people (for whatever reasons) only do so in a subset - some a broader or narrower range than others.
Yes. Also by your personality. One member of my immediate family has a reasonably high mental potential but has been (both by nature and by choice) thumpingly anti-intellectual all their life. Quite competent in a narrow range , functionally a moron in most other respects.