What do we mean when we speak of "the other" and of "othering?" This first part of our two-part series on otherness looks at the question of the other and at the problem of othering through the multiple lenses of psychoanalysis, philosophy and child development. To tell the story, we have drawn from original interviews with psychoanalysts Jessica Benjamin, Cynthia Chalker, George Makari, Donna Orange, John Riker and Robert Stolorow, as well as from interviews with the philosopher Shaun Gallagher, and the child psychologist and psychobiologist Colwyn Trevarthen.