Overview
In Greek mythology, Tiresias was a blind prophet of Apollo in Thebes, famous for clairvoyance and for being transformed into a woman for seven years. He was the son of the shepherd Everes and the nymph Chariclo. Tiresias participated fully in seven generations in Thebes, beginning as advisor to Cadmus himself.
Mythology
Eighteen allusions to mythic Tiresias, noted by Luc Brisson, fall into three groups: the first recounts Tiresias' sex-change episode and later his encounter with Zeus and Hera; the second group recounts his blinding by Athena; the third, all but lost, seems to have recounted the misadventures of Tiresias.
Blindness and gift of prophecy
Like other oracles, how Tiresias obtained his information varied: sometimes, he would receive visions; other times he would listen for the songs of birds, or ask for a description of visions and pictures appearing within the smoke of burnt offerings or entrails, and so interpret them. Pliny the Elder credits Tiresias with the invention of augury.
From Wikipedia (CC BY-SA 4.0).