Credo quia absurdum est

Credo quia absurdum is a Latin phrase that means "I believe because it is absurd." It is a paraphrase of a statement in Tertullian's work De Carne Christi (ca. 203-206), "prorsus credibile est, quia ineptum est", which can be translated: "it is by all means to be believed, because it is absurd". The context is a defence of the tenets of orthodox Christianity against docetism:

The phrase does not express the Catholic Faith, as explained by Pope Benedict XVI: "The Catholic Tradition, from the outset, rejected the so-called “fideism”, which is the desire to believe against reason. Credo quia absurdum (I believe because it is absurd) is not a formula that interprets the Catholic faith."

The phrase is thus sometimes associated with the doctrine of fideism, that is, "a system of philosophy or an attitude of mind, which, denying the power of unaided human reason to reach certitude, affirms that the fundamental act of human knowledge consists in an act of faith, and the supreme criterion of certitude is authority."(Catholic Encyclopedia). It has also been used, though often in different interpretations, by some existentialists.

The phrase is often incorrectly used as an example of the irrationality of religious faith. But in the larger context of Tertullian's overall argument, which is that highly improbable stories are actually unlikely to be fabrications, he is clearly not advocating an irrational approach to faith.

The phrase inspired a celebrated bon mot by H.L. Mencken: "Tertullian is credited with the motto 'Credo quia absurdum'—'I believe because it is impossible'. Needless to say, he began life as a lawyer."

The phrase has also been adopted as the motto for The Ancient and Honorable Order of E Clampus Vitus in modern times.

The phrase was used as an example of zen in D. T. Suzuki's book, Introduction to Zen Buddhism (which was based on essays he wrote in 1914):

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