What life lessons can be found in mythology?

Question

especially greek mythology.

Answer 1

Christians would argue: all of them.

Answer 2

Nearly every one including having s*x with ones mother.....

Answer 3

Don't be overly proud or you will suffer, don't be overly vain or you will suffer, don't be overly greedy or you will suffer, don't defy fate or you will suffer, etc.

Answer 4

Mainly acts of heroism that good triumphs over evil seems to be the prevalent theme running through all.