The Will to Power: An Attempted Transvaluation of All Values. Book III and IV

For the history of the text constituting this volume I would refer readers to my preface to The Will to Power, Books I, and II., where they will also find a brief explanation of the actual title of the complete work.
In the two books before us Nietzsche boldly carries his principle still further into the various departments of human life, and does not shrink from showing its application even to science, to art, and to metaphysics.
Throughout Part I. of the Third Book we find him going to great pains to impress the fact upon us that science is as arbitrary as art in its mode of procedure, and that the knowledge of the scientist is but the outcome of his inexorable will to power interpreting facts in the terms of the self-preservative conditions of the particular order of human beings to which he belongs. In Aphorisms 515 and 516, which are typical of almost all the thought expressed in Part I., Nietzsche says distinctly: The object is not 'to know,' but to schematise,—to impose as much regularity and form upon chaos as our practical needs require.
Unfamiliarity, constant change, and the inability to reckon with possibilities, are sources of great danger: hence, everything must be explained, assimilated, and rendered capable of calculation, if Nature is to be mastered and controlled.
Schemes for interpreting earthly phenomena must be devised which, though they do not require to be absolute or irrefutable, must yet favour the maintenance of the kind of men that devises them. Interpretation thus becomes all important, and facts sink down to the rank of raw material which must first be given some shape (some sense—always anthropocentric) before they can become serviceable.
Even the development of reason and logic Nietzsche consistently shows to be but a spiritual development of the physiological function of digestion which compels an organism to make things like (to assimilate ) before it can absorb them (Aph. 510). And seeing that he denies that hunger can be a first motive (Aphs. 651-656), and proceeds to show that it is the amœba's will to power which makes it extend its pseudopodia in search of what it can appropriate, and that, once the appropriated matter is enveloped, it is a process of making similar which constitutes the process of absorption, reason itself is by inference acknowledged to be merely a form of the same fundamental will.