Read this excerpt from the iliad.

then thus the king: "shall i my prize resign
with tame content, and thou possess'd of thine?
great as thou art, and like a god in fight,
think not to rob me of a soldier's right.
at thy demand shall i restore the maid?
first let the just equivalent be paid
the evidence supports the idea that homer is reflecting the greek emphasis on

selfishness
personal honor
power of the gods