Affirming and denying, appreciating and depreciating, express the will to power just as acting and reacting express force. (And just as reactive forces are still forces, the will to deny, nihilism, is still will to power: ' . . . a will to nothingness, an aversion to life, a rebellion against the most fundamental presuppositions of life; but it is and remains a will!' GM III 28 p. 163) This distinction between two kinds of quality is of the greatest importance and it is always found at the centre of Nietzsche's philosophy. There is a deep affinity, a complicity, but never a confusion, between action and affirmation, between reaction and negation. Moreover, the determination of these affinities brings the whole art of philosophy into play. On the one hand, it is clear that there is affirmation in every action and negation in every reaction. But, on the other hand, action and reaction are more like means, means or instruments of the will to power which affirms and denies, just as reactive forces are instruments of nihilism. And again, action and reaction need affirmation and negation as something which goes beyond them but is necessary for them to achieve their own ends. Finally, and more profoundly, affirmation and negation extend beyond action and reaction because they are the immediate qualities of becoming itself. Affirmation is not action but the power of becoming active, becoming active personified. Negation is not simple reaction but a becoming reactive. It is as if affirmation and negation were both immanent and transcendent in relation to action and reaction; out of the web of forces they make up the chain of becoming. Affirmation takes us into the glorious world of Dionysus, the being of becoming and negation hurls us down into the disquieting depths from which reactive forces emerge.
Gilles Deleuze, Nietzsche and Philosophy pg. 54