 Which of the remaining worlds are indistinguishable? Given that the hen is always clucking, Zoe has information that allows her to distinguish \(w_{1}\) and \(w_{2}\) from \(w_{3}\) and \(w_{4}\) and vice versa, cf. symmetry. Hence, no arrows between these. The worlds \(w_{3}\) and \(w_{4}\) are indistinguishable. This brings us to the following representation: