Kei Hiruta’s study seeks to bring the ideas of the two great twentieth-century political thinkers, Hannah Arendt and Isaiah Berlin, into dialogue with one another. It explores their intellectual engagements with one another, but more importantly, compares their writings on the concepts of freedom and the nature of evil that were fundamental to the work of both theorists. Hiruta offers here an impeccably researched work, providing lucid explanation of the political thought of both Arendt and Berlin, and successfully brings the arguments of both (and their flaws) into sharp relief in his comparative analysis.

Neither Arendt nor Berlin featured the other’s work in their writings to any great extent, even critically. Arendt’s published work, for instance, features just a single footnote referencing Berlin. They had fundamentally different approaches to political thought, one drawing on ancient republican ideas, the other on modern liberalism. They came from different countries (Germany and Russia), emigrated to different countries (the United States and Britain), and did so at different times in their lives and under different circumstances. Moreover, in the interactions that did take place between the two, they “failed disastrously to get along with one another” (p. 8). There is no lengthy story to tell about the personal relationship between the two, nonetheless, Hiruta does an excellent job of setting out what evidence does exist of their opinions of one another. In short, they disliked each other, although the strength of feeling was much greater on Berlin’s side. Arendt was Berlin’s bête noire, in his own words, and comments to friends and correspondents reveal his profound antipathy to Arendt’s ideas. Arendt, for her part, seems rather more indifferent to Berlin. It is also true, as Hiruta explains, that Berlin claimed more than one nemesis, and he was certainly not alone in his disgust toward Arendtian politics (especially after the Eichmann controversy). Given the relatively limited comments on Berlin by Arendt, the historical discussion of their engagement is necessarily somewhat one-sided, as Hiruta freely admits.

For all this, there are, Hiruta argues, significant biographical and philosophical parallels between the two: They have major overlapping political and theoretical concerns, albeit their approach and premises differ in fundamental respects. It is this philosophical story that forms the substance of the book, with the ideas of each used to throw the others’ (contrasting) claims into relief, an approach that proves illuminating, and certainly validates the comparative approach of the text.

Hannah Arendt and Isaiah Berlin is both scholarly and accessible, with succinct and accurate explanations of the overlapping components of Arendt and Berlin’s work. It draws extensively on archival sources, adding color to the histories of this already extensively researched pair. A particular strength of the book is Hiruta’s successful interlacing of biography with philosophy, explaining, for example, how the different experiences of Arendt and Berlin during the Nazi years influenced their writings on the Holocaust. The Russian-born Berlin found what he felt to be a true home in Britain after emigrating as a child, in contrast with Arendt who, as an adult migrant to the United States, remained rooted in German intellectual heritage, whilst being profoundly impressed by the political principles of her adopted home. This contrast offers up an intrinsically interesting story about the different senses of self that emerged from their migrant experiences for Arendt and Berlin, as well as the differences between American and British academia in the mid-twentieth century.

Hiruta marshals Arendt and Berlin’s opposing opinions on the political themes both wrote on: totalitarianism, the nature of evil (including through the prism of the Eichmann trial), their ideas of freedom, and related to all these, the question of what it is to be human. Although the ideas discussed are not new to readers of Arendt or Berlin, Hiruta’s analysis is a helpful aid in grasping the political import of these ideas. He does this by skilfully contextualizing their views, counterposing their biographical experiences, and bringing the ideas of each into greater clarity by contrasting and assessing them against their opponent’s claims, highlighting the omissions and shortcomings of each. For instance, Arendt and Berlin agree, writes Hiruta, that “to be free is to be human in the full sense of the term, and to deprive one of freedom is to deny one’s humanity” (p. 49). Yet their distinct notions of what it means to be human brought them into opposition. Hiruta’s discussion of freedom, one of the two central concepts in the book, is extremely helpful for thinking though what it means for Berlin and Arendt. Equally insightful, his chapter on evil and judgment considers Arendt from the perspective of a moral thinker, something she famously believed should not be part of “political” thinking, and yet, as Hiruta shows, remains a perspective that cannot be discarded. Arendt and Berlin’s different stances on contentious questions, for example, the true nature of Adolf Eichmann, are presented in this work as equally plausible—although genuinely different—interpretations, and the discussion enlivens the thought of both thinkers without closing down the debate in either direction.

Yet the method adopted here, of comparison and distinction between the two authors, can at times be overstated. This is the case in relation to one particular but very significant concept in their work: nationalism. Hiruta positions Arendt and Berlin at two poles: Berlin appeals to a “benign and humane” nationalism, while Arendt, Hiruta claims, rejects nationalism altogether (p. 197). Yet the clarity of this distinction is overemphasized, and Arendt’s position in particular is oversimplified. Arendt was certainly opposed to ethnonationalism, and of course was profoundly opposed to the part nationalism played in the growth of imperialism in the late nineteenth century. Nationalism, in all its forms, is clearly a more passive form of political belonging than the active political membership that Arendt espoused. However, many of her critiques of the nation-state have more to do with her criticism of the state, and the hierarchies of power it perpetuates, than of the nation. That these hierarchies are often accompanied by ethnic nationalism exacerbates and directs the problematic nature of the state. But nationalism—at least in somewhat more benign forms—is not necessarily as fundamentally problematic for Arendt as Hiruta asserts. For example, the cultural nationhood of the Jewish people is praised by Arendt, or at the very least asserted as a fundamental element of what it is to be Jewish. The tragedy of Arendt’s famous pariah/parvenu distinction is precisely that Jewish people were faced with an impossible decision between rejecting their Jewish identity or rejecting the wider political community. Many of the concerns that Arendt had about the creation of Israel relate to the fact that it became a nation-state on the Western model. On the other side of the argument, Berlin’s “benign” nationalism also does not support violent, imperial action. The two thinkers are perhaps not as divided over nationalism as Hiruta suggests here.

Hiruta’s book is superbly researched and written, and its core conceptual analysis of the notions of freedom and evil in the two thinkers is insightful and makes a powerful case for the continued relevance of their ideas. His construction of the debate between these two theorists adds new dimensions to our understanding of Berlin and Arendt’s work, revitalizing the thought of both on the political.