Plagues functioned as a setup for an even more crucial theme in ancient myth: a leader’s intelligence. At the beginning of the “Iliad,” for instance, the prophet Calchas – who knows the cause of a nine-day plague – is praised as someone “who knows what is, what will be and what happened before.” This language anticipates a chief criticism of Homer’s legendary King Agamemnon: He does not know “the before and the after.” – The Conversation