Isaiah Berlin was one of the most influential thinkers of the twentieth century. His most famous essays—“Two Concepts of Liberty,” “The Originality of Machiavelli,” and “The Hedgehog and the Fox”—are touchstones for scholars interested in contemporary liberalism, Renaissance political thought, and Russian intellectual history, and rightly so, since they are provocative works that reframe their subjects in novel ways. Yet anyone who undertakes a study of Berlin's broader views quickly finds an array of writings that range from moral philosophy to music criticism. Part of the attraction of studying Berlin arises not simply from what he says, but from trying to piece together a reading of his work that reconciles all his interests. Two recent additions to the secondary literature, Johnny Lyons's The Philosophy of Isaiah Berlin and George Crowder's The Problem of Value Pluralism: Isaiah Berlin and Beyond, represent such an effort, if in different ways. What is notable is how someone whom Oakeshott once derided as the “Paganini of ideas” continues to be a source of reflection on issues that have only grown more pressing as time passes.

A relative newcomer to the scholarly debates about Berlin, Lyons provides an account that is simultaneously an excavation of Berlin's ideas and a meditation on contemporary philosophy. The disregard of Berlin's abilities as a philosopher is the starting point of Lyons's study, as he finds Berlin's training in philosophy to have informed his writings throughout the course of his life. The goal, then, is to restore Berlin's standing as a philosopher by excavating the philosophical foundations of his position. Lyons regards philosophy as an engagement that involves more than the parsing of terms that is found so frequently today, and instead requires a wholehearted commitment to truth. From this perspective, Lyons interprets Berlin's essays as instances of philosophical inquiry for others to emulate, as they exemplify a searching exploration of questions that are, if not timeless, persistently perplexing. Lyons reads Berlin sympathetically and foregrounds his reliance on Kant and Vico as the basis for his philosophical stance. Attributing to Berlin a transcendental argument concerning the concepts and categories that frame human experience, Lyons highlights the way in which this Kantian impulse is transmuted through the prism of Vico's historicism.

Lyons is well aware of the problems this poses for Berlin—of how this opens him to the charge of relativism—but refrains from following the lead of others whose concern for “logic chopping” leads them to miss the bigger point (118–19). For Lyons, underlying Berlin's views is a commitment to a notion of freedom that grounds human experience, even if Berlin refrains from speaking in terms of an essential human nature. Lyons attributes this to Berlin's interest in Romanticism, and he is comfortable with the degree of ambiguity this introduces into Berlin's thought. Again, the claim is not that Berlin has all the answers, but that he puts the questions in such a way as to entice readers to take them up themselves.

Lyons's reading is particularly earnest—and I will return to this in a moment—but in the main I believe he is correct. Berlin never sets out to systematically answer all the questions he asks, and, contra Oakeshott, this is anything but shallow. Chopin is as creative as Mahler, even as Pascal is as insightful as Hegel. Depth can be expressed in an essay or aphorism as easily as in a tome, perhaps even more so for thoughts that challenge rather than console.

That Berlin's ideas do challenge us is the starting point for Crowder. Whereas Lyons offers a general interpretation of Berlin, Crowder explores the reception of Berlin's work as regards his views of value pluralism. Crowder's book both builds on his own previous research and serves as a review of those following Berlin who are similarly concerned about the implications of value pluralism. Broadly speaking, the concern is twofold: Can value pluralism be distinguished from relativism, and does value pluralism generate a novel account of liberalism? Crowder and most of the scholars he reviews answer yes to both questions, but not without qualification.

Crowder begins by noting that Berlin himself never provided an unequivocal answer to either of these questions, but nevertheless suggests answers that are, once developed, instructive. Issues of context, goods defined as universal in scope, and a commitment to pluralism itself are all options Berlin suggests but refrains from fully exploring, and these serve as the paths Crowder traverses as he considers what has since been said. Eventually Crowder settles on a conceptual account of value pluralism, one that characterizes it in terms of diversity and coherence, taking these to be the appropriate source for arguments in support of autonomy, toleration, and compromise (116). He provides a scrupulous study of the ways each of these notions play into a defense of liberal egalitarianism that is sensitive to democratic procedures, and thus greatly develops Berlin's basic ideas. The end result is a work that underscores Crowder's contribution to the literature on value pluralism, as he both displays a mastery of the debates and his own original views.

Despite their differences, the treatments of Berlin by Lyons and Crowder share some affinities. Both situate Berlin's concern with pluralism in the context of modernity and raise the question whether his defense of liberalism can endure. The implication of their discussions is that it might, so long as the concerns which led to it continue to transfix us. This is, in its way, a fitting response, given the historicist dimensions of Berlin's thought. That noted, the genuine strengths of the texts revolve around the relation of Berlin's ideas to contemporary philosophers, albeit different figures. Crowder focuses on other Berlin scholars, such as Jonathan Riley and William Galston, as well as on the work of Richard Bellamy, John Kekes, Martha Nussbaum, and Bernard Williams. His reading of their works is informative, even setting aside their relation to Berlin. If there is one drawback to his discussion, it is that his conceptual approach seems susceptible to the weakness of all deductive arguments. When value pluralism is defined in such a way as to lead to key components of liberalism, then one cannot help but wonder how things would look if it was defined differently, particularly if value pluralism did not involve a concern for coherence. Crowder notes this objection (136–37), but this may be a bigger problem than he allows.

As regards Lyons, he relates Berlin's arguments directly to those of Richard Rorty, Quentin Skinner, Galen Strawson, and Charles Taylor, as well as various others, such as Hume, Nietzsche, Plato, and Socrates. The sweep is impressive, and it is clear that Lyons has been thinking about these issues for a while. However, if there is a misstep in his discussion, it is the earnestness mentioned before, which leads him to dismiss much of the secondary literature as overly pedantic. This is a bit of a mistake. Lyons's final argument is reminiscent of John Gray's, and fuller treatment of Gray and other Berlin scholars would help clarify the differences between them. Nevertheless, Lyons's book is a noteworthy contribution to Berlin scholarship, and, like Crowder's, merits the attention of anyone interested in these issues.