Martin Heidegger claimed that reason is the “most stiff-necked adversary of thought” and an obstacle to be discarded.
For more on the context for Heidegger’s claim and his contributions to postmodernism, see p. 69 of my Explaining Postmodernism: Skepticism from Rousseau to Foucault. See also:
Heidegger and postmodernism: Includes “Heidegger’s synthesis of the Continental tradition,” “Setting aside reason and logic,” “Emotions as revelatory,” and “Heidegger and postmodernism.”
Heidegger and National Socialism.
Heidegger, anti-humanism, and the Left.
“Heidegger on the Führer Principle.”
Heidegger and World War One — Altman’s book.
Heidegger’s call for “someone capable of instilling terror”.