Impure Reflection
ELI5
Impure reflection is what happens when you look at yourself and, instead of seeing the constant movement and flux that you actually are, you freeze yourself into a fixed thing — a "type," a mood, a personality — as if you were an object you could pin down and describe.
Definition
Impure reflection, as Sartre deploys the term in Being and Nothingness, names the spontaneous but ontologically derivative movement by which the for-itself turns back upon itself and in so doing constitutes the psyche as a quasi-in-itself. It is distinguished from pure reflection, which discloses the for-itself's historicity — its ekstatic, non-objectified self-temporalization — without reifying it. Impure or "constituent" reflection is precisely the operation that projects a stabilized psychic object (an emotion, a state, a character trait) behind the reflected-on, treating what is in fact a pure nihilating process as if it possessed the density and inertia of an in-itself. The psyche, on this account, is not a given depth to be discovered but an artefact produced by this reflective falsification: the for-itself "is-in-order-to-be" its reflected content as in-itself, which is to say it entertains the bad-faith project of being a thing.
The second occurrence sharpens the ontological stakes: as soon as one "enters the plane of impure reflection — that is, of the reflection which seeks to determine the being which I am" — a populated, temporalized world of psychic facts comes into view. Impure reflection is thus the constitutive operation behind what Sartre calls psychic temporality — the successive, linear order of states and qualities — as opposed to original historicity. This means it is not merely an epistemological error but an ontological operation: it is the move that produces the subject-as-object, the ego as quasi-substance, and the dense, peopled world of ordinary psychological self-understanding.
Place in the corpus
The concept lives exclusively within the Sartrean strand of the corpus — specifically in jean-paul-sartre-hazel-barnes-being-and-nothingness-an-essay-on-phenomenological — and functions as a technical articulation of the broader phenomenological ontology of the for-itself. It extends the cross-referenced canonical concept of Reflection by specifying its most common, spontaneous mode: not the pure, non-thetic disclosure of historicity but the reifying gesture that grounds ordinary psychological self-knowledge. In the terms supplied by the Reflection synthesis, impure reflection is precisely what Sartre calls "constituent reflection," which constitutes the psyche as a quasi-in-itself — a structure that parallels the Lacanian mirror-stage capture, where reflective fascination "blocks rather than enables genuine self-knowledge."
In relation to Consciousness, impure reflection marks the point where the for-itself's radical transparency to itself breaks down into the opacity of the psychic object — a move that resonates, from a different direction, with the Lacanian demotion of consciousness to an epiphenomenon of deeper structural processes. Against Subjectivity as a non-totalizable, split position that resists self-coincidence, Sartrean impure reflection names precisely the temptation to totalize: to treat the subject as a determinable being ("the being which I am"). And in its production of a "peopled temporality," impure reflection stands opposed to the authentic Historicity of the for-itself — the ekstatic self-temporalization that the cross-referenced concept of Historicity designates as the for-itself's original mode of being-in-time. Impure reflection is thus the ontological mechanism by which authentic historicity collapses into derivative, objectified psychic succession.
Key formulations
Being and Nothingness: An Essay on Phenomenological Ontology (page unknown)
As soon as we enter on the plane of impure reflection—that is, of the reflection which seeks to determine the being which I am—an entire world appears which peoples this temporality.
The phrase "seeks to determine the being which I am" is theoretically loaded because it captures the constitutive bad faith of impure reflection: the for-itself, which is ontologically indeterminate and nihilating, projects upon itself the project of having a determinate being — a being that "peoples" a world, producing the psychic objects (states, qualities, ego) that fill the temporality impure reflection constructs. The word "peoples" is key: it signals that impure reflection does not merely distort a pre-given psychic content but actively generates a populated quasi-world where none existed at the level of pure historicity.