“Since the 1970s, Calle has repeatedly invited us to question whether artists should be held to the same standards as other people. In viewing her work, we must ask whether invading someone’s privacy or betraying their trust is an acceptable emotional cost to art.” Natasha Bell looks at some of Calle’s most famous projects, similar work by other artists such as Arne Svenson, Dries Depoorter and Santiago Serra, and a graduate-school project of her own that got her an A and lost her a close friend.