To repeat and expand on michelepinto 's and others' proposals:
- The four sides = The four lines of the Tetrapharmakos
- The dot = the atom (or whatever basic building block of matter you want in modern terms)
- The space around the dot represents the void.
- The points at the top (a triangle pointing up) and bottom (a triangle pointing down) of the diamond shape represent pain and pleasure.
- Additionally, the points represent the choices we make based on pain and pleasure. Which way will we decide to go? It's up to us!
- The symbol is an abstract eye to represent the motto SIc fac omnia tamquam spectet Epicurus. You could even include the letters SFOTSE in some arrangements around or inside the diamond.
- The diamond shape with dot is an abstract representation of a walled Garden with a group of people inside.
- For those Epicureans who want to emphasize lathe biosas it can represent that but doesn't need to.
- The two sides of the diamond represent two people facing each other with outstretched arms < > joining hands in friendship.
- The diamond itself represents the most durable natural physical substance which stands for the unshakable enduring trust in the Canon and the physical nature of the Cosmos with no supernatural intervention.
I'm blue-skying here but just wanted to provide in how many directions you can go with a simple figure. I agree with Cassius that the most traditional "symbol" was the bust of Epicurus but that's hard to capture graphically (unless someone is up for a challenge).
I very much miss having a universally agreed upon symbol for Epicurean philosophy, and I quite like the many ways in which this can be interpreted.
One practical problem is, of course, having actual space between the four sides and the dot in a real-world pendant like a necklace, but I think an diamond-shaped piece of gold/silver (ideally with raised edges) with a stone set in the middle should do fine?
What would we call this symbol?