It seems unlikely that Calvinball is a nomic. Instead Calvinball appears to be more like Mornington Crescent, in that players are all participating in creating a mutually satisfying fiction, Calvinball's fiction looks like a complicated ballgame, Mornington Crescent more cerebral but since in both cases there aren't actually any set rules the game is not about changing the rules. Rosalyn eventually figures out how to play Calvinball well just as players can get "good" at Mornington Crescent with experience.
