I do not fear as to the proof of my proposition, but I shall aim higher, I shall try to demonstrate by the overwhelming weight of facts. Proof produces belief, demonstration knowledge. The innocent have been hanged on the evidence of proof, but a fact is established by demonstration. Demonstration follows proof, and knowledge follows belief; and ascending from the individual to mankind, we find the age of reason to succeed the age of faith. Science dwells in demonstration, and establishes principles from observed facts. Why may there not be a scientific criticism? To arrive at this the writer must ascend to that eminence in feeling where the opposing prejudices of mankind can not reach him; he must rise above praise or censure, he must dwell alone in the light of reason, he must be a child of Truth. Vain, however, would it be to expect to find himself or a public devoid of prejudice. This is impossible, for prejudice is produced by strong conviction. It is a feeling which, like a magnet, points as the electric force directs. To counteract this force is to destroy the magnet. It is those who think deeply, and have investigated thoroughly, who have an enlightened prejudice, and those who take upon authority what others tell them, who have a blind prejudice; but those who neither think nor investigate for themselves may truly be said to have no prejudice. My object is to convince the understanding and thereby build up a prejudice in favor of my proposition, which shall have a foundation of fact and argument, not to be removed, and to be but little disturbed. The world is my jury, they shall decide upon the facts. Lord Bacon gave the world a _method_, this method is also mine: LET FACTS REVEAL THE INWARD TRUTH OF NATURE. MYSTERY.