A process of self-identification in which a subject assumes an identity they mistake for their own. The concept derives from Jacques Lacan's account of the mirror stage of childhood development in which the young child (under 18 months) sees itself in the mirror and mistakes that image for itself. While the image in the mirror is obviously an image of them, it isn't actually them, but the child fails to make this distinction. Thus the child's ‘I’ is the product of its imaginary and the result of an illusion. Marxist critic Louis Althusser adapts this idea in the development of his concept of interpellation, which holds that society constantly calls on its subjects to adopt a particular identity (citizen, consumer, voter, etc.). But in doing so the subject is alienated from their ‘true’ self.