wearing or publicly displaying a 20er moon with four dots on it, for example.
I think that this is an interesting investigation. Everyone will have unique ideas for what symbolizes Epicurean philosophy. It may take time for those who feel similarly (to wear or display) to discover what feels right for them. Perhaps everyone has their own personal "Epicurean symbol". We can have multiple symbols, but I think all "Epicureans" should be able to recognize the symbol without further explanation - because the symbol "should" (lol, in my opinion) clearly reflect an Epicurean idea. And so I think the four dots requires one Epicurean to explain to another Epicurean what it means, so for me personally it doesn't work (just my opinion).
Here are some more ideas for symbols (ideas rather than finished symbols, and so the atom could end up being rendered differently):
The atom itself:
The atom in the 20er moon: