“…The request/server cooperation semantics will be described as the follow (The detail of the axiom described in reference [4]): SF(Request(Joe, Jane, Wait(Joe),s))≡ ∃ s1,s*.Do(Joe, Jane, Walk-toward(Jane),,s1) ∧s1<s*∧ SF(Promises(Jane, Joe, Wait(Joe)),s*) (…”