Retortion is the act of identifying a self-referential contradiction in an opponent's position.
So, for example, if I were to write, "No one can type a coherent sentence in English," a thoughtful critic might retort: "But what you just wrote provides evidence against what you claim to be true."
Retortion is spelled "retorsion" in French. The idea of turning an opponent's self-referential contradictions into a reason for rejecting the position is common among Transcendental Thomists, who used various forms of this argument to demonstrate the instability of Kant's epistemology.
- St. Augustine, De Trinitate, 12-21; De Civitate Dei, XI, 26
- Si fallor, sum.
- Cogito, ergo sum.
- Heidegger, Intro to Metaphysics, 199
- "No one can jump over his own shadow."
- I know this is true. I know what a shadow is, I know what jumping is, and I see what he means. I don't know how to specify the premises that would turn this into a formal deduction, but I'm sure they could be spelled out eventually.
Actions speak louder than words.
Part of our human condition.
We say things to each other in body language.
We read meanings in each other's bodily expressions.
Retortion compares a tacit action to the content of an articulation.
What is done differs from what is said.
What is done is known by a knower.
It is not reflected in the words spoken or the judgment made.
Those with eyes to see and ears to hear can recognize the performative contradiction.
The person who says one thing while doing another that is self-referentially inconsistent may be utterly unaware of the contradiction. They are focused on what they are saying, not on the action by which the judgment is made and sustained.