Performative contradiction are performative contradictions in this context. Habermas claims that post-modernism's epistemological relativism suffers from a performative contradiction. Hans-Hermann Hoppe claims in his theory of argumentation ethics that arguing for any political position other than free-market anarchism results in a performative contradiction. Jaakko Hintikka more rigorously fleshed out the notion of performative contradiction in analyzing Descartes' famous "cogito ergo sum" argument, concluding that "cogito ergo sum" relies on performance rather than logical inference. Performative contradiction A performative contradiction () arises when the propositional content of a statement contradicts the presuppositions of asserting it. An example of a performative contradiction is the
Cogito, ergo sum and let him deceive me as much as he can, he will never bring it about that I am nothing, so long as I think that I am something. So, after considering everything very thoroughly, I must finally conclude that the proposition, "I am, I exist," is necessarily true whenever it is put forward by me or conceived in my mind. (AT VII 25; CSM II 16–17) There are three important notes to keep in mind here. First, he claims only the certainty of "his own" existence from the first-person point of view — he has not proved the existence