“The portrait. That’s something old, one might say,” wrote Vincent van Gogh in a letter of 1889, “but it’s also brand new.” Using the self-portraits of van Gogh as a throughline, this exhibition examines the shifts and epiphanies that mark the portrait’s march into modernity. On view are 75 works by van Gogh, Edvard Munch, Berthe Morisot, Gustave Courbet, Helen Schjerfbeck, and many others. They hold much more information than simply the features of a face. —E.C.