in particular, the claim that Heidegger's critique of reason is to blame for his political errors by pointing out that committed "rationalists" among the German philosophers were prone to the same errors. Sluga's book seeks to show that the willingness to involve themselves politically not only Heidegger, but also of Neo-Kantians like Bruno Bauch, Neo-Fichteans like Max Wundt, and Nietzscheans like Alfred Baeumler was ultimately due to their misconceived belief that they were living through a moment of world-historical crisis in which they were particularly called upon to intervene. His book Politics and the Search for the Common Good seeks to re-think politics in substantially new terms. Sluga distinguishes in it between a long tradition of "normative political theorizing" that ranges from Plato and Aristotle through Kant to contemporary writers like John Rawls and a more recent form of "diagnostic practice" that emerged in the 19th century and whose first practitioners were Karl Marx and Friedrich Nietzsche. Diagnostic political philosophy, Sluga argues, does not seek to establish political norms through a process of abstract philosophical reasoning but seeks to reach practical conclusions through a careful diagnosis of the political realities. Identifying himself with this strand of political philosophizing, Sluga proceeds to examine the thinking of Carl Schmitt, Hannah Arendt, and Michel Foucault as 20th century exemplars of the diagnostic approach. The book seeks to highlight the promise and the achievements of the diagnostic method as well as its shortcomings so far and its inherent limitations. In doing so, Sluga maps out an understanding of politics that makes use of some of Wittgenstein's methodological concepts. He characterizes politics as a family resemblance phenomenon and argues that the concept of politics does not identify a natural kind. It is therefore also mistaken to assume that there is a single common good at which all politics aims. Similarly, we must forgo the belief that there is a best form of government (as, e.g., democracy). Politics must, rather, be conceived as a continuous search for a common good which can have no final, conclusive answer. It is a sphere of uncertainty in which we operate always with a radically incomplete and unreliable picture of where we are and with only shifting ideas of where we want to go. The institutional forms that this search takes will change over time. Sluga agrees with other diagnostic thinkers that the classical institution of the modern state is