_John 3:3—_“Except one be born anew, he cannot see the kingdom of God.” The spiritual ages make most progress in theology,—witness the half-century succeeding the Reformation, and the half-century succeeding the great revival in New England in the time of Jonathan Edwards. Ueberweg, Logic (Lindsay’s transl.), 514—“Science is much under the influence of the will; and the truth of knowledge depends upon the purity of the conscience. The will has no power to resist scientific evidence; but scientific evidence is not obtained without the continuous loyalty of the will.” Lord Bacon declared that man cannot enter the kingdom of science, any more than he can enter the kingdom of heaven, without becoming a little child. Darwin describes his own mind as having become a kind of machine for grinding general laws out of large collections of facts, with the result of producing “atrophy of that part of the brain on which the higher tastes depend.” But a similar abnormal atrophy is possible in the case of the moral and religious faculty (see Gore, Incarnation, 37). Dr. Allen said in his Introductory Lecture at Lane Theological Seminary: “We are very glad to see you if you wish to be students; but the professors’ chairs are all filled.” III. Relations of Material to Progress in Theology. (_a_) _A perfect system of theology is impossible._ We do not expect to construct such a system. All science but reflects the present attainment of the human mind. No science is complete or finished. However it may be with the sciences of nature and of man, the science of God will never amount to an exhaustive knowledge. We must not expect to demonstrate all Scripture doctrines upon rational grounds, or even in every case to see the principle of connection between them. Where we cannot do this, we must, as in every other science, set the revealed facts in their places and wait for further light, instead of ignoring or rejecting any of them because we cannot understand them or their relation to other parts of our system.