KEITH CHRISTIANSEN: This is Gustave Moreau’s fantastic vision of the ancient Greek hero Oedipus, on the right, staring down the winged Sphinx. Rebecca Rabinow recounts their story: REBECCA RABINOW: Oedipus was on his way to save the City of Thebes when he encountered the monstrous sphinx. He had to answer her riddle correctly or he would be killed. The riddle was: what goes on four legs in the morning, on two at noon and on three in the evening? The answer is a man who crawls on all four as a baby, walks on two legs as an adult and walks with a cane in old age. If you look in the foreground you'll see the hand and a foot of a cadaver and you'll also see the crown of a king and the laurel wreath of a hero, who failed to answer the riddle correctly. Moreau loved color and used it throughout his pictures. He also had great fondness for elaborate ornamental detail. Take, for example, the urn on the column at right. It's intricately depicted. Although Moreau painted hundreds of pictures, he's perhaps best remembered as a teacher of a group of artists that included Henri Matisse. They all felt that Moreau had done so much to further their art because he encouraged them to find their own styles.