This trick has only one way in. Is there no other way out? Take the police as an example. Using traditional heuristics, policemen can spot any dead volcano -- as long as it never decides to trap them in. Is there no other way out? Take the police as an example. Using traditional heuristics, policemen can spot any dead volcano -- as long as it never decides to trap them in.

     Is there no other way out? Take the police as an example.