PerspectivismNietzsche claimed the death of God would eventually lead to the loss of any universal perspective on things, and along with it any coherent sense of objective truth. Nietzsche himself rejected the idea of objective reality arguing that knowledge is contingent and conditional, relative to various fluid perspectives or interests. This leads to constant reassessment of rules (i.e., those of philosophy, the scientific method, etc.) according to the circumstances of individual perspectives. This view has acquired the name perspectivism.
In Thus Spoke Zarathustra, Nietzsche proclaims that a table of values hangs above every great person. He points out that what is common among different peoples is the act of esteeming, of creating values, even if the values are different from one people to the next. Nietzsche asserts that what made people great was not the content of their beliefs, but the act of valuing. Thus the values a community strives to articulate are not as important as the collective will to see those values come to pass. The willing is more essential than the intrinsic worth of the goal itself, according to Nietzsche. "A thousand goals have there been so far," says Zarathustra, "for there are a thousand peoples. Only the yoke for the thousand necks is still lacking: the one goal is lacking. Humanity still has no goal." Hence, the title of the aphorism, "On The Thousand And One Goals". The idea that one value-system is no more worthy than the next, although it may not be directly ascribed to Nietzsche, has become a common premise in modern social science. Max Weber and Martin Heidegger absorbed it and made it their own. It shaped their philosophical and cultural endeavor, as well as their political understanding. Weber for example, relies on Nietzsche's perspectivism by maintaining that objectivity is still possible—but only after a particular perspective, value, or end has been established.
Among his critique of traditional philosophy of Kant, Descartes and Plato in Beyond Good and Evil, Nietzsche attacked thing in itself and cogito ergo sum (I think, therefore I am) as unfalsifiable beliefs based on naive acceptance of previous notions and fallacies. Philosopher Alasdair MacIntyre puts Nietzsche in a high place in the history of philosophy. While criticizing nihilism and Nietzsche together as a sign of general decay, he still commends him for recognizing psychological motives behind Kant and Hume's moral philosophy:
For it was Nietzsche's historic achievement to understand more clearly than any other philosopher...not only that what purported to be appeals of objectivity were in fact expressions of subjective will, but also the nature of the problems that this posed for philosophy.