Bearded, bundled in his greatcoat, the young man stares defiantly at passersby as if to say that although he is only 19, he already knows that he will dominate the art world for the rest of his life. If anyone doubts the implicit truth of Pablo Picasso's 1901 self-portrait, he has only to walk farther into Paris' new Picasso Museum, which opened last week. There, spread out like all the treasures from Aladdin's cave, are the gems of nearly three-quarters of a century of labor: 228 paintings, 149 sculptures, nearly 1,500 drawings and just as many engravings.
The museum is perhaps...