Now it is those deeper and wider questions, which can be answered only by the discovery of the _more remote_ and _ultimate_ reasons and causes of things, that philosophy undertakes to investigate, and—as far as lies within man’s power—to answer. No one has ever disputed the supreme importance of such inquiries into the ultimate reasons and causes of things—into such questions as these, for instance: What is the nature of man himself? Has he in him a principle of life which is spiritual and immortal? What was his first origin on the earth? Whence did he come? Has his existence any purpose, and if so, what? Whither does he tend? What is his destiny? Why does he distinguish between a right and a wrong in human conduct? What is the ultimate reason or ground of this distinction? Why have men generally some form or other of religion? Why do men generally believe in God? Is there really a God? What is the origin of the whole universe of man’s experience? Of life in all its manifestations? Has the universe any intelligible or intelligent purpose, and if so, what? Can the human mind give a certain answer to any of these or similar questions? What about the nature and value of human _knowledge_ itself? What is its scope and what are its limitations? And since vast multitudes of men _believe_ that the human race has been specially enlightened by God Himself, by Divine Revelation, to know for certain what man’s destiny is, and is specially aided by God Himself, by Divine Grace, to work out this destiny—the question immediately arises: What are the real relations between reason alone on the one hand and reason enlightened by such Revelation on the other, in other words between natural knowledge and supernatural faith?