Any given teacher can only impart what [s]he knows (or thinks)
So what does the 'smartest' or 'most-knowledgeable' AI actually look like?
I disagree. This is not how knowledge works.
You can learn new things yourself. When under instruction, you may notice nuance your teacher has not mentioned, and may be unaware of. There is also learning without instruction.
Call that "self teaching" maybe? Saves your aphorism but it still a strawman question.
For an AI to be self-learning, it will have to have a lot more senses and opportunity to manipulate and observe the world on its own, than anyone seems to want to give them.
>You can learn new things yourself...There is also learning without instruction.
That means you have found a different "teacher"
Any given teacher can only teach what they know
You are describing finding other teachers :)
Which is, of course, how learning in gestalt works: but you can still only learn to the limit of any given teacher (even if combined puts you ahead of any single one of them)
Ways of learning, methods of discovery, etc can be learned - but as to knowledge, you cannot exceed what any given teacher teaches from the teacher ... which is precisely how this post started :)