Nietzsche saw that a science of conduct based on natural and physiological laws was a possible and logical thing. And in him, for the first time in the history of philosophical thought, do we find a scholarly and at the same time an intellectual critic of authorised standards. The biological point of view was never lost sight of by him. If at times he seemed to abandon it, it was but for a brief period; he ever came back to it. Even his most abstract passages have their feet implanted in the fact that all phenomena are answerable to the law of vital fitness. Before the tribunal of biology Nietzsche arraigns and tries every phase of his thought, whether it deals with physical phenomena, ethical conduct or with abstract reasoning. Philosophy, for centuries divorced from science, is here clothed in the garments of scientific experimentation; a relationship is established between these two planes of rationalism and empiricism which have always been considered by other thinkers as detached and unrelated. Nor does Nietzsche ally himself, either consciously or unconsciously, with such philosophers as Bruno and Plato (who stood between the scientific thinkers on the one hand and the abstract dialecticians on the other), and attempt a formulation of a system of thought founded on intuitive processes. Such poetic conceptions had no fascination for him except as they were directly applicable to the problem of the universe. Those men who busied themselves with the mere theory of knowledge he held as supererogatory cobweb-spinners; and even in the realm of metaphysicians such as Descartes, Spinoza and Leibniz, he dallied but casually. His aim was to relate all thought to determinable values of life. In his introduction Nietzsche calls morality the Circe of philosophies, and adds: "For, to what is it due that, from Plato onwards, all the philosophic architects in Europe have built in vain?" Later beneath his analysis--which never assumes the negative qualities of the metaphysical--the moral phenomenon goes to pieces, not by a few simple strokes, nor yet by the effrontery of cynicism or pessimism, but by the most careful and intricate surgery. He points out the great heretics of history as examples of the men who, looked at through the eyes of contemporaries, were "wicked" men, but who, under different environmental circumstances, were considered "good." He denies the static hypothesis on which morality is built, and postulates the theory that immorality is not without its place in the development of the reason. He is constantly attempting to translate the existing moral values into terms of their true nature, not necessarily into immoralities, but into natural unmoralities. The accepted virtues, such as pity, honesty, faith, obedience, service, loyalty and self-sacrifice, are questioned in their relation to racial needs; and modern attitudes toward all human activities are traced to their causes and judged as to their influence.