THE GREEK HEROES 129 man is not able, either by wisdom or by strength, to carry out his own plans in opposition to the will and predestination of the gods. On the contrary, the very prudence that strives to render of none effect such de- crees of the gods as have been announced by oracles or other signs helps to fulfill the divine will. This appears most simply in the oldest part of the cycle, the expedi- tion of the Seven against Thebes, described in the Thebais. A later counterpart is the expedition of the Epigoni (' the after-born 7 ) ; and the same thought is brought out in a more complicated manner in the Oedi- pus myth, which contains the preliminary history of this contest, and which Cinaethon of Sparta (?) had used in his Oidipodeta. Finally, the Alkmaionis, a sequel to the story of the Epigoni, and a work belonging to the end of the sixth century B.C., described the tremendous punishments inflicted by the gods in avenging the murder of relatives. In the extant Thebais of the Roman poet Statius the principal ideas of all these lost epics are combined. But this group of myths is still further per- fected from the purely moral point of view in the Attic tragedy, and is represented in the following extant plays : the ' Seven against Thebes ; of Aeschylus, the 'Oedipus Tyrannus/ ' Oedipus at Colonus/ and ' An- tigone 7 of Sophocles, the 'Phoenissae' of Euripides. 168. According to a divine decree Laius, the son of Labdacus, was to be the last of the family of Cadmus who should be king of Thebes. Therefore he received from the oracle at Delphi the utterance : " If thou beget a son, he will murder thee and marry his own mother." So when his wife locaste, whom the epic poets called Epicaste, the sister of Creon, the last of the Sparti,
