It is hardly possible to give practical information on the methods of psychic defence without at the same time giving practical information on the methods of psychic attack. It is not without reason that initiates have always guarded their secret science behind closed doors. To disclose sufficient to be adequate without disclosing sufficient to be dangerous is my problem. But as so much has already been made known concerning the esoteric teachings, and as the circle of students of the occult is becoming rapidly wider every day, it may well be that the time has now come for plain speaking.