Philosophy and science have always been based on the idea that the world of appearances is an illusion that both reveals and conceals an underlying reali-ty. In many instances, this idea has been attached to mystical systems of thought, as in some Eastern philosophies that view reality as a play of fictions manifested by a universal mind. In the West, it has been the intellectual under girding for rationalism and empiricism, which have given rise to contemporary science and social science. First we should understand the main principles and iss ....