Followup to the original thread:
I think there is - though I cant really say where - examples of epicureus or at least ancient epicureans say its prudent to say that at the point we dont know the answer to this problem though it surely is one. I think there is two important things to say about the atomism point that everyone can have an opinion on in addition to what Cassius Amicus mentions - 1) if something is put forth that is in direct conflict with observable reality (like I would say part of quantum mechanics is) then there is something wrong with the theory, not nature. A cat is either dead or alive thats observable logic. 2) there is no need to go to any supernatural explanation just because the exact nature of the phenomena is unknown. We dont know why eels migrate as they do but there is nothing indicating its supernatural. Some day we might know. Surely the nature of existence has greater implications but the logic is the same. We dont assume supernatural eel-explanations as we have no indication of this (and if we had that would change the nature of nature just as much). Same - that we dont know exactly the nature of the substance of nature does not make the direct (or indirect) empirism of epicureanism less valid. I even think that the epicurean atoms more represent a concept then an exact description but that is a more diffuse argument and not really the essence of the matter I would say. Hope this has some validity for you