Ok I think I accept Feynman's answer, that we can keep asking "why" ad nauseam after hearing "they do". But his appeal is not to something deep and mysterious, instead to something so shallow and readily apparent that it gets taken for granted.
I don't think that's quite what he is saying. He is saying that the underlying phenomena is so deep and mysterious that to truly understand it requires appealing to logic and analysis techniques that fall very far outside our ordinary, everyday intuition.
I thought something along similar lines at first, penning up that Feynman's reply basically boils down to "I don't know, but I know more than you and until you know as much as me you won't know as much as me." - which is 'feyn', of course. But it didn't fit with my next thought, saying the deeper phenomenon that is being questioned is actually the simplest, so I had to change.
I think the interviewer asked the 'wrong' question; starting with the nature of a fundamental force is at the wrong end to ever be satisfied by a sequence of whys. It's not far off asking "I've got an electron in each hand, I bring them together and they repel - why?". I guess that's why Feynman initially looks a bit perturbed, then does an admirable job at lashing an answer together on the spot.
In which case it is as much (I think more) about saying he doesn't know, than saying it is hard to understand or unintuitive.
For all its mystery, gravity is readily apparent and gets taken for granted, I imagine it would have got a similar response if only for completeness. I think it's just that most people in this world will leave unsatisfied after having just learnt the ultimate truth (or something near it) of our physical world, if that truth is "don't know, it just does". So it needs dressing up (or down), to satisfy the human psyche. Gravity maybe less so, because someone is less likely to ask.
But yes, there's no way he's going to be able to explain the "how" component of the question to an untrained audience in a few minutes - how it all interrelates and behaves to the limits of his understanding.
"Magnets are magnetic because they're made up of lots of little magnets."
That might do!
... until one really dives into the experiments and mathematics that predict the phenomena (and having to ignore all the devices we use whose operation was engineered from the physics). ...
Generally agree, except the bit I put in italics. I have seen that argument pop up a few of times in the thread - that in essence electrical engineering and especially its advanced results (like iPhones) exist because of physics and academia. AFAIK the physics has usually lagged behind the industrial R&D, except in the early days when there was no commercial application, and a few notable examples (like radio, bad exapmle the iPhone then). Providing enormous support - but playing catch-up to empirical discoveries or very incomplete theories.
My point there is if humanity were somehow limited in its ability to produce high-level physicists and mathematicians (which isn't too much of a stretch if one considers how unlikely that seems in the first place), then we'd still have self-aligning gate CMOS, it just wouldn't be 2nm. There is really little standing in the way of that Apple M1 Ultra MCM, given enough 'tinkering' - it's practically how the semiconductor industry advances anyway. Radio would have been discovered by now. I can get by without Maxwell's equations, and although I'd make a pretty poor RF designer, I still know what I'm doing enough to make things work well enough.
You can make a picture that explains one aspect of the phenomena but the power of Maxwell's Eqs is that it is predictive of ALL (in the classical limit) electromagnetic phenomena.
I can't work out whether I agree or disagree. Which doesn't bode well for my point, which was something Maxwell-sounding but simpler to understand.
If the speed of sound were fixed or you could have Cherenkov radiation in a vacuum, I'd tend to agree.