Zen

Strange that the 'mondai' (riddles) of Zen Buddhism contain references to both trees and handclapping (does a falling tree make a noise with no-one to hear it – and what sound would one hand clapping make...?) As I remember it, the Bible has the best solution to these hypothetical questions: when the Kingdom of God comes on earth, all the trees (or those that are left after Man's destructive reign) will burst out clapping and singing...And I expect you'll hear it to the ends of several universes!!