Alterity is a philosophical term meaning "otherness", strictly being in the sense of the other of two (Latin alter). In the phenomenological tradition it is usually understood as the entity in contrast to which an identity is constructed, and it implies the ability to distinguish between self and not-self, and consequently to assume the existence of an alternative viewpoint. The concept was established by Emmanuel Lévinas in a series of essays, collected under the title Alterity and Transcendence (1999[1970]).
The term is also deployed outside of philosophy, notably in anthropology by scholars such as Nicholas Dirks, Johannes Fabian, Michael Taussig and Pauline Turner Strong to refer to the construction of "cultural others". The term has gained further use in seemingly somewhat remote disciplines, e. g. historical musicology where it is effectively employed by John Michael Cooper in a study of Goethe and Mendelssohn.