To prove, means, in the proper sense of the word, to test, to bring ideas, opinions, and beliefs to the ordeal of reason, of accepted standards of judgment. It is a criticism of the mind and its operations, and hence it may easily happen that to prove is to weaken and unsettle. In what is most vital, in belief in God, immortality, and freedom of the will, in religion and morality, our faith is stronger than any proof that may be brought in its defence; and this is not less true of our faith in the reality of nature and the laws of science; and when this is made plain by criticism, those whose mental grasp is weak or partial, are confused and tempted to doubt. They are not helped, but harmed, and our ceaseless discussions and provings, in press and pulpit, are the source of much of the unrest, religious doubt, and moral weakness of the age. The people need to be taught by those who know and believe, not by those whose skill is chiefly syllogistic and critical. Philosophic speculation is like a vast mountain into which men, generation after generation, have sunk shafts in search of some priceless treasure, and have left in the materials they have thrown out the mark and evidence of failure. But the noblest minds will still be haunted by the infinite mystery which they will seek in vain to explain. Their faith in reason, like that of the vulgar, cannot be shaken, nor can defeat, running through thousands of years, enfeeble their courage or dampen their ardor. Let our increasing insight into Nature's laws fill us with thankfulness and joy. It is good, and makes for good. Let us bow with respect and reverence before the army of patient investigators who bring highly disciplined faculties to bear upon the most useful researches. Let knowledge grow. A nearer and truer view of the boundless fact will not make the world less wonderful, or the soul less divine, or God less adorable. If one should declare that it is contrary to the teachings of faith to hold that conversation may be carried on by persons a thousand miles apart, it would be sufficient to reply that such conversation takes place, and that to attempt to annul fact by doctrine is absurd. There is no excuse for the controversial conflict between science and religion; for science is ascertained fact, not theory about fact, and when fact is rightly ascertained it is accepted of all men. The most certain fact, for each one, is that he knows and loves, and that this power comes to him through communion with what is higher and deeper and wider than himself,--with God.