Phineus, the son of Agenor, was a king of Thrace and a prophet. Because he prophesied too truly, revealing too much of the gods' truth to humans, Zeus blinded him and set the Harpies to plague him. Whenever Phineus sat down to eat, the Harpies would swoop down and steal the food; what little food they left would be foul-smelling and unpalatable. When Jason and the Argonauts arrived in Phineus' land, they rid his household of the curse by having the winged Boreads pursue the Harpies; the goddess Iris prevented the Boreads from killing the Harpies by promising that Phineus would not be troubled again. In return for the Argonauts' help, Phineus foretold the results of their quest, and revealed to them how they should get past the hazard of the Symplegades.