“What of Art?
-It is a malady.
--Love?
-An Illusion.
--Religion?
-The fashionable substitute for Belief.
--You are a sceptic.
-Never! Scepticism is the beginning of Faith.
--What are you?
-To define is to limit.”

Meine Skepsis bewahrt mich davor, Fanatiker zu werden wovor noch kein Glaube geschützt hat.
deschner.info http://www.deschner.info/index.htm?/de/person/zitate.htm

Source: Nauti Dreams

Source: Mystery and Manners: Occasional Prose

Anti-Religious Thought In The Eighteenth Century http://www.cse.dmu.ac.uk/~mward/gkc/books/anti_religious_thought.txt; first published in "An Outline of Christianity : The Story of our Civilization", Vol. IV, Christianity and Modern Thought (1926)

Books, Tricks of the Mind (2006)

Source: He Still Moves Stones

On the advisableness of improving natural knowledge (1866) http://www.gutenberg.org/dirs/etext01/thx1410.txt
1860s
Context: The improver of natural knowledge absolutely refuses to acknowledge authority, as such. For him, scepticism is the highest of duties; blind faith the one unpardonable sin. And it cannot be otherwise, for every great advance in natural knowledge has involved the absolute rejection of authority, the cherishing of the keenest scepticism, the annihilation of the spirit of blind faith; and the most ardent votary of science holds his firmest convictions, not because the men he most venerates hold them; not because their verity is testified by portents and wonders; but because his experience teaches him that whenever he chooses to bring these convictions into contact with their primary source, Nature — whenever he thinks fit to test them by appealing to experiment and to observation — Nature will confirm them. The man of science has learned to believe in justification, not by faith, but by verification.

Source: The Final Empire

Source: The Complex Vision (1920), Chapter I
Context: My answer to the question "Why do we philosophize?" is as follows. We philosophize for the same reason that we move and speak and laugh and eat and love. In other words, we philosophize because man is a philosophical animal.… We may be as sceptical as we please. Our very scepticism is the confession of an implicit philosophy.