“The refusal of free inquiry derives from an awareness of the fragility of the basis of religious faith; and since certainty is psychologically preferable to truth, the former often being willfully mistaken for the latter, anything that threatens certainty is anathematized with fury.”

La jalousie se nourrit dans les doutes, et elle devient fureur, ou elle finit, sitôt qu'on passe du doute à la certitude.
Maxim 32.
Reflections; or Sentences and Moral Maxims (1665–1678)

The Case for God, first broadcast on BBC1, 6 September 2010

11 August 1972; p. 90
1970's, Conversations with Samuel Beckett and Bram van Velde (1970 - 1972)

Source: A Treatise On Political Economy (Fourth Edition) (1832), Introduction, p. xv

In Search of a Better World (1984)
Context: There are uncertain truths — even true statements that we may take to be false — but there are no uncertain certainties.
Since we can never know anything for sure, it is simply not worth searching for certainty; but it is well worth searching for truth; and we do this chiefly by searching for mistakes, so that we have to correct them.

Source: God's Problem: How the Bible Fails to Answer Our Most Important Question - Why We Suffer

Introduction to Absurd Drama (1965)
Context: The Theatre of the Absurd attacks the comfortable certainties of religious or political orthodoxy. It aims to shock its audience out of complacency, to bring it face to face with the harsh facts of the human situation as these writers see it. But the challenge behind this message is anything but one of despair. It is a challenge to accept the human condition as it is, in all its mystery and absurdity, and to bear it with dignity, nobly, responsibly; precisely because there are no easy solutions to the mysteries of existence, because ultimately man is alone in a meaningless world. The shedding of easy solutions, of comforting illusions, may be painful, but it leaves behind it a sense of freedom and relief. And that is why, in the last resort, the Theatre of the Absurd does not provoke tears of despair but the laughter of liberation.