This phase of the subject is, however, of little importance compared with the mental effects produced by the too persistent exercise of the subjective faculties in the production of phenomena. Again we must draw our illustrations from spiritistic circles. It is undeniable that the tendency of mediumship is to unhinge the mind, to destroy the mental balance, and often to produce the worst forms of insanity. And it is noticeable that the more thoroughly sincere the medium is in his belief in the genuineness of his power to evoke the spirits of the dead, the greater is the tendency to insanity. The reason is obvious. If he sincerely believes himself to be under the control of an extraneous power, he yields implicit obedience to that power; especially if it assumes to be a superior mentality, as it generally does. Instead of assuming control of the power, he allows it to control him. As a matter of course, he is ignorant of the laws pertaining to it. He is ignorant of the fact that the force which controls him resides within himself, and is not a superior being commissioned from Heaven to convey a message from the Source of all knowledge. He is dazed by its wonderful exhibitions of superior intelligence, is captivated by its eloquence, and awed by its assumption of authority. In short, he knows nothing of its source, or the limitations of its powers of reasoning. The result is that he yields implicit obedience to its guidance in all things. His reason has abdicated its throne and abandoned its functions, and he is at the mercy of his subjective mind, which, in turn, is controlled by the false suggestions of his own disorganized and subjugated objective intelligence. His physical degeneracy keeps pace with his mental decline, his whole nervous system is prostrated by excessive exercise of subjective power, and too frequently the end is acute mania or drivelling imbecility.