According to the philosophy of Zen, we are too much of a slave to the conventional way of thinking, which is dualistic through and through. No “interpenetration” is allowed, there takes place no fusing of opposites in our everyday logic. What belongs to God is not of this world, and what is of this world is incompatible with the divine. Black is not white, and white is not black. Tiger is tiger, and cat is cat, and they will never be one. Water flows, a mountain towers. This is the way things or ideas go in this universe of the senses and syllogisms. Zen, however, upsets this scheme of thought and substitutes a new one in which there exists no logic, no dualistic arrangement of ideas. We believe in dualism chiefly because of our traditional training. Whether ideas really correspond to facts is another matter requiring a special investigation. Ordinarily, we do not inquire into the matter, we just accept what is instilled into our minds; for to accept is more convenient and practical, and life is to a certain extent, though not in reality, made thereby easier. We are in nature conservatists, not because we are lazy, but because we like repose and peace, even superficially. But the time comes when traditional logic holds no more true, for we begin to feel contradictions and splits and consequently spiritual anguish. We lose trustful repose which we experienced when we blindly followed the traditional ways of thinking. Eckhart says that we are all seeking repose whether consciously or not, just as the stone cannot cease moving until it touches the earth. Evidently, the repose we seemed to enjoy before we were awakened to the contradictions involved in our logic, was not the real one, the stone has kept moving down towards the ground. Where then is the ground of non-dualism on which the soul can be really and truthfully tranquil and blessed? To quote Eckhart again, “Simple people conceive that we are to see God as if He stood on that side and we on this. It is not so; God and I are one in the act of my perceiving Him.” In this absolute oneness of things Zen establishes the foundations of its philosophy.