IB Philosophy 1.1 Identity Key Definitions

Consciousness: the state of subjective awareness in which an individual experiences thoughts, sensations, and perceptions with a first-person, qualitative character: the 'what it is like' quality of mental life.

A constitutive belief is one so central to a person's self-understanding that abandoning it would fundamentally alter who they take themselves to be, regardless of whether the belief is empirically true or false.

A person's cultural identity is the sense of belonging and self-understanding derived from membership in a particular cultural group, shaped by shared language, traditions, values, and social practices. It functions not merely as a label but as a framework through which the individual interprets their experience and relates to others.

Numerical identity is the philosophical claim that a person or object at one time is literally one and the same individual as that person or object at another time, not merely similar to it. This is contrasted with qualitative identity, which only requires sharing the same properties.

Personal identity is the philosophical question of what makes a person the same individual over time and what constitutes the fundamental nature of the self, asking not just how we recognise people in everyday life but what metaphysically constitutes personhood and the conditions for its persistence.

Personhood is the status of being a person, typically defined by possessing certain capacities such as self-consciousness, rationality, moral agency, or social recognition, though the criteria vary across philosophical traditions.

Psychological continuity, associated with John Locke, is the view that personal identity consists in overlapping chains of memory, consciousness, and psychological connection linking earlier and later stages of a person's life, prioritising mental over physical continuity as the criterion of personal identity.

Qualitative identity is the relation between two things that share the same properties or characteristics without being the same individual, contrasted with numerical identity. For example, two identical twins are qualitatively identical but numerically distinct, being two separate persons.

The body theory of personal identity holds that a person persists over time in virtue of the continuity of their physical body, so that what makes you the same person tomorrow is the ongoing existence of the same biological organism. The view faces challenges from thought experiments involving brain transplants, where our intuitions about identity seem to track the brain rather than the body as a whole.

The soul theory of personal identity holds that what persists through change is an immaterial, non-physical soul that constitutes the true self and survives bodily death. While the view provides a straightforward account of post-mortem survival, it faces the objection that an unobservable soul offers no empirical criterion for re-identifying the same person across time.