architectural and engineering science could teach them nothing. I ask, also, if it is possible to find a region in the subconsciousness which is common to two people, why is it absurd to suggest that there might be a region common to a man and a horse? Why is this any more absurd than that they should eat the same food and breathe the same air and feel the same affection and be frightened at the same dangers? The only persons who will be dogmatic about such subjects are the persons who are ignorant. Those who take the trouble to investigate, discover more wonderful things every day, and they realize that we have here a whole universe of knowledge, to which we have as yet barely opened the doors. Consider, for example, the facts which we are acquiring on the subject of personality and what it means. You would say, perhaps, that if there is anything you know positively, it is that you are one person, and have never been anybody else, and that your body belongs to you, and that nobody else ever has used or ever can use it. But what would you say if I told you that tomorrow "you" might cease to be, and somebody else might be in possession of your body, walking it around and wearing its clothes and spending its money? What if I were to tell you that there might be in "you," or in your body, half a dozen different personalities which you have never known or dreamed of, and that tomorrow there might break out a war between them and "you," as to which of the half dozen people should hear with your ears and speak with your tongue and walk about with your clothes on? Unless you are familiar with the literature of multiple personality, you would surely say that this was unbelievable--quite as much so as a mathematical horse! Let us begin with the case of the Reverend Ansel Bourne, who was many years ago a perfectly respectable clergyman in a Rhode Island town. One day he disappeared, and his family did not hear of him. A year or two later there was a store-keeper in a town in Pennsylvania, who suddenly came to himself as the Reverend Ansel Bourne, not knowing what he had been in the meantime, or how he came to be keeping a store. Under hypnotism it developed that he had in him two personalities, and his trance personality recollected all that had been happening in the meantime and told about it freely.