From 1912 to 1951, Barnes amassed one of the world’s greatest private collections of modern European artwork—more Cézannes (69) and Renoirs (an absurd 181) than any other museum; Matisse’s game-changing The Joy of Life ; Seurat’s extraordinary Models ; the list goes on and on. The Barnes Foundation was officially an educational institution, but was effectively one of America’s first museums of modern art. (The New York organization that put capital letters on those words is four years younger.) But if Barnes’s collection is a model to emulate, the saga of his organization is a lesson in founder’s-syndrome perils.