In the poem "The Iliad," I feel that the over-arching theme is selfishness. Nearly everything bad that happens within the pages happen as a result of someone's selfishness. In fact, the Trojan War itself is a War of selfishness.
The selfishness of Paris and Helen begin the war, proper.
The selfishness of Agamemnon incites it further.
The selfishness of Achilles leads the Greeks toward defeat.
The selfishness of Hector leaves Andromache alone with Astyrnax.
While it is simple to say that in a different time one can attribute each of these actions with a different motivation:
Or a need to defend personal honor
It is important to remember that this is a tale for the ages, and the moral of The Iliad are as dynamic as the times in which we read them.
But, the question I pose is, is there a catalyst? Whose selfish act ultimately creates the chain-reaction of selfish acts?
So long as this story exists, we as humans, will find new morals to attribute to it.