 Stirner extends this critique to the work of all the left-Hegelians, including those with whom he had associated in Berlin. Although they disagree about the content of human nature—for “political liberals” like Arnold Ruge human nature is identified with citizenship, for “social liberals” like Moses Hess human nature is identified with labour, and for “humane liberals” like Bruno Bauer human nature is identified with critical activity—all the left-Hegelians are said to have reproduced the basic Feuerbachian error: separating the individual from his human essence, and setting that essence above the individual as something to be striven for. In contrast, Stirner maintains that because it has no universal or prescriptive content, human nature cannot ground any claim about how we ought to live. His own intellectual project—which he describes as an attempt to rehabilitate the prosaic and mortal self, the “un-man”(124) for whom the notion of a calling is alien—is intended as a radical break with the work of these contemporaries.