Is science really gaining in its assault on the totality of the unsolved? As science learns one answer, it is characteristically true that it also learns several new questions. It is as though science were working in a great forest of ignorance, making an ever larger circular clearing within which, not to insist on the pun, things are clear... But as that circle becomes larger and larger, the circumference of contact with ignorance also gets longer and longer. Science learns more and more. But there is an ultimate sense in which it does not gain; for the volume of the appreciated but not understood keeps getting larger. We keep, in science, getting a more and more sophisticated view of our essential ignorance.

From: "A Scientist Ponders Faith," Saturday Review, 3 (January 1959), as cited in: F.A. Hayek, Ronald Hamowy. The Constitution of Liberty: The Definitive Edition. 2013, p. 77.