[MaxBarraclough]

I'm always surprised how rarely anyone makes the obvious point here, and sure enough in this thread it looks like no-one has: no, you can't explain complex things to a two year old. Not without dumbing it down to the point that you've discarded everything of value.

Is this some odd kind of hyperbole about teaching techniques? I don't see that it's helpful.

If I'm struggling with it, the odds of a toddler being able to comprehend it are slim to none.

The kernel trick? Quantum computing? Even good old eigenvectors? (Or, heaven forbid, genuinely advanced mathematics?)

The best professors in the world couldn't convey these things to a 2 year old, and not for lack of understanding.