Euthanasia of Reason

The "euthanasia of reason" is Copjec's Kantian-inflected formulation for the theoretical impasse that arises when thinking attempts to grasp sex as its proper object. Borrowed from Kant (who used the phrase to name the self-dissolution of pure reason when it transgresses the limits of possible experience into antinomy), the phrase is here redeployed to name the constitutive failure that theory encounters when it attempts to totalize sex within the field of signification. Copjec's theoretical move is precise: the impasse is not a contingent shortcoming of our theories that better constructions might overcome, but a structural necessity. Sex is produced precisely by the internal limit of signification — the point where the signifier fails to close upon itself — and not by some positive substance that signifiers then fail to capture. Both the dogmatic-structuralist position (sex as a fixed symbolic structure) and the skeptical-constructivist position (sex as indefinitely open to resignification, à la Butler) are symmetrical evasions of this impasse: they each offer a way to make reason survive — either by granting it a stable object or by relieving it of any determinate object at all. The "euthanasia of reason" names the third, properly Lacanian path: reason must undergo its own dissolution as the price of thinking sex at all, because the antinomy sex generates cannot be resolved by either horn.

This concept thus designates not an epistemological failure but an ontological-structural condition. The antinomy that sex produces — parallel to Kant's mathematical antinomies — is irreducible. Reason does not merely run into an external wall; it encounters its own constitutive limit immanently, from within, and in doing so exhausts itself. This is the "euthanasia" — a controlled, necessary dying-away of reason's legislative ambitions when confronted with the Real that sex names.

This concept belongs to Copjec's sustained argument in radical-thinkers-joan-copjec-read-my-desire-lacan-against-the-historicists-verso, where she defends a Lacanian account of sex against Butlerian constructivism. It is most directly an extension and specification of the canonical concepts of Contradiction and Reason (cross-referenced here), and it also implicates Not-all, Feminine Sexuality, Language, and Performative Signification. The "euthanasia of reason" names the moment at which the antinomy internal to sex — precisely the kind of constitutive, irresolvable contradiction that Hegel and Lacan identify as structural rather than accidental — defeats reason's attempt at theoretical closure. This aligns with the corpus account of Contradiction as the condition of possibility that cannot be sublated, and with the Lacanian account of Language as constitutively failing to inscribe the sexual relation.

The concept functions as a specification of the antinomial structure of sexuation (cross-referenced through Not-all and Feminine Sexuality): the not-all, which prevents the totalization of the feminine position, is precisely what reason cannot master without destroying itself in the attempt. As against Butler's performative constructivism (cross-referenced as Performative Signification), which treats the instability of signification as license for voluntary resignification, Copjec here insists that the failure of signification is structural — a Real limit, not a discursive opportunity. In this way, "euthanasia of reason" functions as the epistemological-critical counterpart to the ontological claim about sex and the Real: it describes what happens to theory when it honestly confronts the limit that sexuation imposes. The Kantian borrowing is crucial, since it frames the antinomy of sex on the model of the Kantian mathematical antinomies — irresolvable not because of insufficient data, but because reason has overstepped its own proper domain.

Read My Desire: Lacan Against the HistoricistsJoan Copjec · 2015 (page unknown)

a growing sense that in theorizing sex we are engaged in a kind of 'euthanasia of pure reason.' I borrow this last phrase from Kant

The phrase "euthanasia of pure reason" is theoretically loaded because "euthanasia" signals not accidental failure but a necessary, self-administered dissolution — reason does not simply stop at a wall but actively expires in its encounter with sex's antinomial structure — while "pure reason" marks this as a Kantian-transcendental claim: it is reason in its legislative, totalizing capacity that cannot survive, not merely this or that inadequate theory.