I was thinking about this just last night. One of my favorite books is called "Architecture of Matter", it's a history of ideas about matter. One early idea w

I was thinking about this just last night. One of my favorite books is called "Architecture of Matter", it's a history of ideas about matter. One early idea was that matter is made of little tiny bits of stuff and that qualities of these little bits (such as being smooth or spikey) leads to macroscopic phenomenon (like spikey bits being acidic.) The problem with this idea (and almost all others) is that it's just pushing the problem down a level: If matter is made out of little bits of matter, what are the little bits of matter made of? FWIW, the wave-particle duality gets around this self-reflexive problem. Matter is made out of some other kind of stuff. But then, as you say, we still have the essential problem of "wtf is this stuff?" but we don't worry about that so much as long as our math describes the behavior of the stuff. > They're not wrong, but it feels rather unsatisfying. IMHO there have been a couple avenues worth exploring that are being largely ignored. What avenues? (Genuinely curious, not trolling.) It seems to me that the ultimate, existential question of what "stuff" actually is, is unanswerable (within the logical/scientific framework.)