What any given prisoner doesn't know is whether they themselves are one of the green-eyed people the others are keeping track of until as many nights have passed as the number of prisoners on the island.
Amit egyikük sem tud, hogy ő vajon a zöld szeműek közé  tartozik-e, akiket a többiek figyelnek, amíg el nem telik annyi éjszaka,  ahány fogoly van a szigeten.