Identical twins, Cathleen and Colleen Wade, 7, were spotted by Arbus at a Christmas party for twins and triplets.

Two years before she received her first camera, Diane Arbus wrote: “There are and have been and will be an infinite number of things on Earth. Individuals all different, all wanting different things, all knowing different things, all loving different things, all looking different. . . . That is what I love: the differentness.” Arbus’s appreciation for the unusual, eccentric, and extraordinary led her to photograph a range of subjects over the thirty years of her career—transvestites, giants, art philanthropists, nudists, and, as here, identical twins. No one knows how Arbus learned about a small-town Christmas party in 1967 being held for local twins and triplets, but it is in keeping with her interest in how people are who they are. Isolating these seven-year-old girls against the wall of the Knights of Columbus hall in Roselle, New Jersey, and photographing them in her typically straightforward manner, Arbus ensured close attention would be paid to the details: the matching homemade dresses (which were green but appear black), the lace stockings bunched below the knees, and the barely discernible difference in each girl’s presentation before the camera. Such details variously belie and reinforce the uncanny suggestion of two thoroughly identical individuals.