Perhaps Nietzsche's greatest philosophical legacy lies in his 20th century interpreters, among them Pierre Klossowski, Georges Bataille, Leo Strauss, Alexandre Kojève, Michel Foucault, Gilles Deleuze (and Félix Guattari), and Jacques Derrida. Foucault's later writings, for example, adopt Nietzsche's genealogical method to develop anti-foundationalist theories of power that divide and fragment rather than unite politics (as evinced in the liberal tradition of political theory). The systematic institutionalisation of criminal delinquency, sexual identity and practice, and the mentally ill (to name but a few) are examples used to demonstrate how knowledge or truth is inseparable from the institutions that formulate notions of legitimacy from 'immoralities' such as homosexuality and the like (captured in the famous power-knowledge equation). Deleuze, arguably the foremost of Nietzsche's interpreters, used the much-maligned 'will to power' thesis in tandem with Marxian notions of commodity surplus and Freudian ideas of desire to articulate concepts such the rhizome and other 'outsides' to state power as traditionally conceived.
Certain recent Nietzschean interpretations have emphasized the more untimely and politically controversial aspects of Nietzsche's philosophy. Nietzschean commentator Keith Ansell Pearson has pointed out the absurd hypocrisy of modern egalitarian liberals, socialists, feminists and anarchists claiming Nietzsche as a herald of their own left-wing politics: "The values Nietzsche wishes to subject to a revaluation are largely altruistic and egalitarian values such as pity, self-sacrifice, and equal rights. For Nietzsche, modern politics rests largely on a secular inheritance of Christian values (he interprets the socialist doctrine of equality in terms of a secularization of the Christian belief in the equality of all souls before God" (On the Genealogy of Morality, Ansell-Pearson and Diethe, eds., Cambridge University Press, 1994, p. 9). Works such as Bruce Detwiler's Nietzsche and the Politics of Aristocratic Radicalism (University of Chicago Press, 1990), Fredrick Appel's Nietzsche Contra Democracy (Cornell University Press, 1998), and Domenico Losurdo's Nietzsche, il ribelle aristocratico (Turin: Bollati Boringhieri, 2002) challenge the prevalent liberal interpretive consensus on Nietzsche and assert that Nietzsche's elitism was not merely an aesthetic pose but an ideological attack on the widely held belief in equal rights of the modern West, locating Nietzsche in the conservative-revolutionary tradition.