At this once-in-a-lifetime exhibition, Picasso Sculpture, at the Museum of Modern Art through February 7, 2016, the viewer is treated to wonderful insights into the artist’s work. It's an epic showing of 140 pieces, arranged chronologically, with the sculptures occupying the museum’s entire fourth floor. What becomes clear as you walk from gallery to gallery is that sculpting was an integral, if spasmodic,  part of Picasso'slife. In 1902, at the age of twenty and still living in Barcelona, he created a clay model known as Seated Woman. Five years on, Picasso would have a mind-altering moment when he visited the collection of African and Oceanic sculptures at the Musée du Trocadero in Paris.  That visit, which came at the suggestion of the great painter André Derain, stimulated the young Picasso to try his hand at wood carving.