Published in two parts in 1548 and 1552, Le Quart Livre is Rabelais's last book of certain authenticity and his most difficult and mysterious work. In it, Pantagruel and Panurge undertake a sea voyage and a quest for "the word of the Divine Bottle," but the islands they visit along the way are inhabited by strange beings whose nature and physiognomy defy natural categories. Expressing the elderly writer's despair at the failure of all his dreams as a young humanist, the voyage traces the last phase of the heroic quest, the cycle of old age and death. It is a descent into the underworld, but one that is undertaken hopefully, for the Quart Livre continues the search for a wife and for paternity begun in the Tiers Livre. Ultimately, all of these strivings may be associated with the writer-physician who faces misfortunes in order to cure them. In the end, the Quart Livre affirms the healing power of wine, laughter, and words.