"In 1917, working alone in a remote Swiss asylum, psychiatrist Hermann Rorschach devised an experiment to probe the human mind: a set of ten carefully designed inkblots. For years, he had grappled with the theories of Freud and Jung while also absorbing the aesthetic movements of the day, from Futurism to Dadaism. A visual artist himself, Rorschach had come to believe that who we are is less a matter of what we say, as Freud thought, than what we...