As commonly used, individual refers to a person or to any specific object in a collection. In the 15th century and earlier, and also today within the fields of statistics and metaphysics, individual means "indivisible", typically describing any numerically singular thing, but sometimes meaning "a person." (q.v. "The problem of proper names"). From the seventeenth century on, individual indicates separateness, as in individualism. Individuality is the state or quality of being an individual; a person separate from other persons and possessing his or her own needs, goals, and desires.

Descartes

In his statement Cogito ergo sum ("I think therefore I am"), Rene Descartes posits the notion the individual subject, distinct from the world around him or her. This is the most famous articulation of subject-object dualism (see subject-object problem) in the Western philosophical tradition.

Empiricism

Early empiricists such as Ibn TufailG. A. Russell (1994), The 'Arabick' Interest of the Natural Philosophers in Seventeenth-Century England, pp. 224-262, Brill Publishers, ISBN 9004094598. and John Locke introduced the idea of the individual as a tabula rasa ("blank slate"), shaped from birth by experience and education. This ties into the idea of the liberty and rights of the individual, society as a social contract between rational individuals, and the beginnings of individualism as a doctrine.

Hegel

Hegel regarded history as the unfolding of God's plan through a process of thesis, antithesis, and synthesis. The role of the individual in this view was as an agent of this unfolding--a part of a greater whole.

Existentialism

With the rise of existentialism, Kierkegaard rejected Hegel's notion of the individual as subordinated to the forces of history. Instead, he elevated the individual's subjectivity and capacity to choose his or her own fate. Later Existentialists built upon this notion. Nietzsche, for example, examines the individual's need to define him/her own self and circumstances in his concept of the will to power and the heroic ideal of the Übermensch. The individual is also central to Sartre's philosophy, which emphasizes individual authenticity, responsibility, and free will. In both Sartre and Nietzsche, the individual is called upon to create his or her own values, rather than rely on external, socially imposed codes of morality.

Martin Buber's I and Thou

In I and Thou, Martin Buber presents the individual as something that changes depending on how he or she is relating to the outside world, which can be in one of two ways: In the I-it relation, the individual relates to the external world in terms of objects that are separate from him or herself (an "I" looking at an "it"). In the I-thou relation, the individual has a personal connection to the external, and feels almost a part of whatever he or she is relating to; the subject-object dichotomy disappears (see Nondualism).