In many of the tasks of life the first step costs the great effort, and the investigation of truth in the higher regions of Nature justifies the familiar maxim. The first step for the modern inquirer is that which carries his consciousness across the threshold of matter into the invisible world. Never mind for the moment whether occult progress be attempted by a direct onslaught on the defences of the invisible world, or by purely internal combats with the desires of the lower self. The unseen must first become a reality for anyone who seriously desires to enter into relations with it, whether he sets his will to work to vanquish his own frailties, or the forces of Nature on the astral plane. An internal struggle with material desire undertaken for a spiritual purpose, just as much as the other kind of contest, is a recognition of the superior realm; and it is not a struggle of the kind we are contemplating at all, if it is merely undertaken for a worldly purpose, as thrifty habits may be cultivated, for instance, at the bidding of the grossest material selfishness. But though a recognition of the invisible world must in this way have been forced, at an early stage of his inquiry, on the mind of everyone who becomes an earnest explorer of Nature’s higher laws, its invisibility is a terrible barrier in the way of the progress that would otherwise be made by the throngs of intelligent materialists who people civilised countries at this epoch of our history. From the point of view of conventional thinkers—of those alike who sacrifice their Sunday mornings to provide for the contingency that there may be something in religion after all, and of those who are frankly incredulous of any Nature lying beyond the reach of instrumental research—a tremendous revolution in all their views of life is accomplished if they are somehow brought face to face with the reality of super-material phenomena, if they ever discover the invisible world and come to know it, or any part of it, as an unequivocal fact.