Now I laugh at my fear of analysis. Most people’s possession of knowledge deprives them of the sense of wonder, but such a sense of wonder and mystery is like the savage’s fear of mysterious fire until he discovers the principle of it and the mastering of it. I say that after we know all there is to know, there is still mystery and wonder of a deeper kind.

Anaïs Nin (1903-1977) Catalan-Cuban-French author, diarist

Diary (1932-11-27)
    (Source)

Source of the more commonly encountered paraphrase (e.g.):

I have no fear of clarity. The possession of knowledge does not kill the sense of wonder and mystery. There is always more mystery. I have no fear of analysis. The possession of knowledge does not destroy the sense of wonder and mystery.