Reason, therefore, is so far from being able to help man to that knowledge, which his nature and condition wants, that it can only help his ignorance to increase and fructify in doubts, fictions, and absurd debates. And the thing cannot be otherwise; man must walk in a vain shadow, so long as reason is his oracle. For nothing can act suitably to nature, find its true state in nature, or answer the end of its creation by the power of reason; because reason is not the life, the power, or former of nature; and therefore has no more power over nature, than over the powers and principles of vegetation, either in the body of man, or any other creature. He therefore who turns to his reason, as the true power and light of his nature, betrays the same ignorance of the whole nature, power, and office of reason, as if he was to try to smell with his eyes, or see with his nose. For as each of these senses has only its one work or power, which it cannot alter, or exceed; so reason has only its one work or power, which it cannot alter, or exceed; and that one work is, to be a bare observer and comparer of things that manifest themselves to it by the senses. This is as much its one only power, as seeing is the one only power of the eyes. When therefore reason takes upon it to determine on things not manifested to it by the senses, as to judge about divine new birth, a divine light, and divine faith; or how the soul wants, or does not want God. it is then as much out of its place and office, as the eye that takes upon it to smell; and its true name and nature is, whim, humor, caprice, conjecture, opinion, fancy, and every other species of blindness, and passion.