Planck on the scientific virtue "akin to" faith

PLANCK:  ". . . The difficulty which organized religion finds in appealing to the people nowadays is that its appeal necessarily demands the believing spirit, or what is generally called Faith.  In an all-around state of scepticism this appeal receives only a poor response.  Hence you have a number of prophets offering substitute wares.

MURPHY:  "Do you think that science in this particular might be a substitute for religion?

PLANCK:  "Not to a sceptical state of mind; for science demands also the believing spirit.  Anybody who has been seriously engaged in scientific work of any kind realizes that over the entrace to the gates of the temple of science are written the words:  Ye must have faith.  It is a quality which the scientists cannot dispense with. . . .
     ". . . As a matter of fact, Kepler is [on the contrary] a magnificent example of [this]. . . .  [W]hat rendered him so energetic and tireless and productive was the profound faith he had in his own science, not the belief that he could eventually arrive at an arithmetical synthesis of his astronomical observations, but rather the profound faith in the existence of a definite plan behind the whole of creation. . . .  Compare him with Tycho de Brahe.  Brahe had the same material under his hands as Kepler, and even better opportunities, but he remained only a researcher, because he did not have the same faith in the existence of the eternal laws of creation.  Brahe remained only a researcher; but Kepler was the creator of the new astronomy. . . .
     ". . . if we did not have faith but could solve every puzzle in life by an application of the human reason what an unbearable burden life would be.  We should have no art and no music and no wonderment.  And we should have no science; not only because science would thereby lose its chief attraction for its own followers—namely, the pursuit of the unknowable—but also because science would lose the cornerstone of its own structure, which is the direct perception by consciousness of the existence of external reality.  As Einstein has said, you could not be a scientist if you did not know that the external world existed in reality; but that knowledge is not gained by any process of reasoning.  It is a direct perception and therefore in its nature akin to what we call Faith.  It is a metaphysical belief.  Now that is something which the sceptic questions in regard to religion; but it is the same in regard to science.  However, there is this to be said in favour of theoretical physics, that it is a very active science and does make an appeal to the lay imagination.  In that way it may, to some extent, satisfy the metaphysical hunger which religion does not seem to be capable of satisfying nowadays.  But this would be entirely by stimulating the religious reaction indirectly.  Science as such can never really take the place of religion.  This is explained in the penultimate chapter of [Where is science going?]."

     Max Planck as interviewed by James Murphy in "Epilogue:  a socratic dialogue:  Interlocutors:  Einstein—Planck—Murphy," in Max Planck, Where is science going?, trans. & ed. James Murphy (London:  George Allen & Unwinn Ltd, 1933), 214-215, 218-219.