Castor and Pollux horse breaker and the boxer / Polydeuces, my brothers" ..." – Helen, "Iliad" 3.253–255), but in the "Odyssey" they are treated as alive even though "the corn-bearing earth holds them". The author describes them as "having honour equal to gods", living on alternate days because of the intervention of Zeus. In both the "Odyssey" and in Hesiod, they are described as the sons of Tyndareus and Leda. In Pindar, Pollux is the son of Zeus while Castor is the son of the mortal Tyndareus. The theme of ambiguous parentage is not unique to Castor and Pollux; similar characterisations appear in
Leda and the Swan many versions of the story, Zeus took the form of a swan and seduced Leda on the same night she slept with her husband King Tyndareus. In some versions, she laid two eggs from which the children hatched. In other versions, Helen is a daughter of Nemesis, the goddess who personified the disaster that awaited those suffering from the pride of Hubris. The subject was rarely seen in the large-scale sculpture of antiquity, although a representation of Leda in sculpture has been attributed in modern times to Timotheus ("compare illustration, below left"); small-scale sculptures survive showing both reclining and standing