Out of all the ideas posted on this thread, the two that I'm throwing my support behind are:
1) Moon, Fish, Ocean being a so-called Zen variation of Rock Paper Scissors, where the disciple must have a certain non-attachment to the outcomes of each play in order to be mindful to grab the pebble and ultimately win whenever the master plays Ocean.
2) With the backwards text and all, realizing that fish backwards is HSIF (Hybrid Systems Interchange Format), defined on
http://repo.isis.vanderbilt.edu/definitions/ as "an interchange format for hybrid system models that can be shared between modeling and analysis tools. HSIF models represent dynamic systems, whose dynamics includes both continuous and discrete behaviors."
"Both continuous and discrete behaviors" sounds to me like dynamics that a robot would need to be mindful of, so to speak, if it were to play Moon, Fish, Ocean. A more specific prediction of game rules, I won't suggest, but I've heard that with the new control systems robots can communicate with each other, so maybe that will be a factor as well.