• Rational thinking which is free from assumptions ends therefore in mysticism. To relate oneself in the spirit of reverence for life to the multiform manifestations of the will-to-live which together constitute the world is ethical mysticism. All profound world-view is mysticism, the essence of which is just this: that out of my unsophisticated and naïve existence in the world there comes, as a result of thought about self and the world, spiritual self-devotion to the mysterious infinite Will which is continuously manifested in the universe.

    Albert Schweitzer: Rational thinking which is free from assumptions ends therefore in mysticism. To relate oneself in the spirit of reverence for life to the multiform manifestations of the will-to-live which together constitute the world is ethical mysticism. All profound world-view is mysticism, the essence of which is just this: that out of my unsophisticated and naïve existence in the world there comes, as a result of thought about self and the world, spiritual self-devotion to the mysterious infinite Will which is continuously manifested in the universe.
    "Philosophy of Civilisation". Book by Albert Schweitzer, Vol. 2 : Civilization and Ethics, Preface, 1949.