As Descartes wrote, "the certitude and truth of all science depend on knowledge of God and on that alone" for "the certitude of all other truths is so dependent on this one that without the knowledge of God it would be impossible ever to know anything else."
Religion and Culture, Christopher Dawson, New York: Meridian, 1958, "Natural Theology as the classical theology of humanism", 7 (pages 4-5 in the google edition CUA Press 2013 link above).
[T]he specific nature of the religious phenomenon...[is that a]ll religion is based on the recognition of a superhuman Reality of which man is somehow conscious and towards which he must in some way orientate his life. The existence of the tremendous transcendent reality that we name GOD is the foundation of all religion in all ages and among all peoples. Ibid., 25.
The [self-satisfied rationalist, confident that he has mastered the secrets of the universe], has focused all his attention and all his activity on the region which can be explored by human reason and controlled by human will, and has thereby made it wider and more habitable, but he has not changed the fact of its ultimate limitation. In so far as he is content to live within this world of his own creation--the artificially lit and hygienically conditioned City of Man--he is living precariously on a relatively superficial level of existence and consciousness, and the higher he builds his tower of civilization the more top-heavy it becomes. For his nature remains essentially the same as that of primitive man--the nature of a rational animal, limited internally by the conditions of his consciousness and externally by his dependence on non-human forces which transcend his animal existence. Ibid., 28-29.