The title of Peter Steinberger’s Rationalism in Politics signals a direct engagement with Michael Oakeshott’s (1962) famous essay of the same name. But where Oakeshott is one of the many thinkers who believe politics is fundamentally not about rational argumentation, evidence, and reason giving, Steinberger mounts a defense for just that view. Politics, he argues, is essentially and in the first instance about claims with “propositional content”: “a structure of truth-oriented argumentation deeply implicated in the rational pursuit of propositions about how things in the world really are” (p. 6).

Steinberger says his is a minority view, and hence necessary. Oakeshott wrote in the previous century, but Steinberger points to the many ways in which “non- and antirationalist” (p. 5) views are again dominant. The beginning of the book canvasses these views in many different strands of political theory: in Hannah Arendt, and the voluminous scholarship her work still inspires; in the more recent “aesthetic,” “affective,” and “post-humanist” turns; and even in contemporary cognitive science and neuroscience, some of which has informed political theorists (he mentions William Connolly’s 2002 book Neuropolitics). Steinberger grounds his own argument on mid-to-late twentieth-century analytic philosophy, on approaches he calls “post-Kantian” and which he argues contemporary political theorists should engage more actively.

Some philosophers in that tradition, too, have rejected rationalism. It is in fact debates among analytic philosophers that frame Steinberger’s discussion in the first two of the three-chapter book. In modern analytic epistemology and the philosophy of mind, the debate has been between “internalism” and “externalism,” which means a debate about what beliefs are and whether cognition is, at least in principle, accessible and intelligible to the person doing the thinking. The internalists say it is; externalists deny this. The latter call the internalist position “the myth of the mental.” Although Steinberger focuses on analytic philosophers—people such as W. V. O. Quine, Wilfred Sellars, Hilary Putnam, Donald Davidson, John Searle, and more recently Robert Brandom and John McDowell—he points to the ways in which thinkers more familiar to political theorists embrace externalist views: most notably Martin Heidegger, as well as contemporary political theorists such as Linda Zerilli and Sharon Krause.

In chapter 1, Steinberger’s approach is primarily critical: he aims to show why many thinkers in the now-capacious categories of externalism and nonrationalism actually presuppose rationalist commitments. This is the basis for his argument in chapter 2: if even externalists end up presupposing “a system of truth-claims, a conceptual apparatus, a universe of discourse” (p. 114), then perforce all thought and action must fundamentally be “a rational enterprise.”

One valuable contribution of the book is to cut across many distinctions and cleavages familiar to political theorists. The rationalism Steinberger offers has little to do with those practices of deliberative democracy critics disparage as a vision of politics as a graduate seminar. It has even less to do with and makes no assumptions about individual rationality. Steinberger even rejects normative and methodological individualism (pp. 168–70). He argues that thinkers as different as Arendt and John Rawls make the same mistake of failing to understand that politics is fundamentally rationalist, with metaphysical commitments.

All this is valuable, whether one agrees with Steinberger or not. I wonder whether the critical engagement convinces readers. Steinberger’s argumentative strategy particularly in the first chapter is common in much analytic philosophy: he takes up a position held by a foil, considers its implications, and adduces a counterexample that calls either some of the implications or the presuppositions of the position into question. Having spent my academic training in that world, I cannot recall that strategy often changing minds. It is a question of the sociology of knowledge about what kinds of arguments end up winning debates. Even in science—understood in the broad German sense of Wissenschaft, which includes most disciplines—rational arguments seldom carry the day, or carry the day alone. That need not be a failure because arguments, like Steinberger’s, nevertheless may advance the discussion. If the nonrationalists are as dominant as Steinberger says they are, it is good to cast a skeptical eye.

And there is much merit to his argument, at least if one shares some of Steinberger’s post-Kantian commitments (as I do). First, there is no thought-independent access to the world: we cannot prove (as philosophers such as Plato or Descartes thought we could) anything with certainty about a mind-independent world. The second is that we can only make sense of the mind-independent world with the concepts we have. This leads to a rationalism where truth claims are warranted when they are consistent with the wide system of beliefs we have, some explicit but most either tacit or implicit.

But what does this mean for politics? Steinberger gets to this explicitly in chapter 3. Politics as a rationalist enterprise means that “political activity is just the attempt to arrive at coherent and argumentatively justified answers to difficult questions of public consequence” (p. 146). He does not deny that people engage in politics for self-interested or aesthetic reasons or even entirely thoughtlessly. Even then, he argues, the engagement is intelligible as political action only against an unavoidable propositional content about the world—that is, beliefs about the way the world is or the way it ought to be. Even when the agent herself is not conscious of that belief, the action is subject to rational reconstruction.

Some readers will find this a thin ledge from which to launch either a concrete political argument or an argument about politics in a pluralistic society. Vaccines work and anthropogenic climate change is real, but the Socratic elenchus Steinberger occasionally seems to propose (p. 161) as our tool feels inadequate against staunch and so often irrational refusals by those who deny both. Still, I find it hopeful to think there is a need for rational justification in our debates even with all the burdens of judgment our messy psychologies put in our way.

It takes some effort to appreciate the book. At times, Rationalism in Politics is not very reader-friendly. Steinberger explicitly says the book is meant for political theorists (p. ix), but I wonder how many are as familiar with the analytic philosophy debates as he seems to assume. Sometimes, he very helpfully lays out an idea or a particular philosopher’s position, but equally often he writes in a conceptual shorthand that may leave a reader reaching for the Stanford Encyclopedia of Philosophy. For example, “Gricean flouting” (p. 70), “Gettier problems” (p. 98), and even “Kant’s third antinomy” (p. 154) probably ought to be explained and not just mentioned. This air of writing for those already in the know is exacerbated by the almost total absence of first names in Steinberger’s prose. By itself, this is minor (and may well be an editorial decision by the publisher), but the effect for some readers may be alienating. It will also be confusing for those readers who mistakenly think the analytic philosopher Strawson whom Steinberger discusses is the contemporary Galen Strawson, a frequent contributor to the Times Literary Supplement, and not Galen’s late father, P. F. Strawson.

Despite these challenges, the payoff of Steinberger’s book is an appreciation of a kind of rationalism that is subtler than critics from Oakeshott onward have claimed. It would be facile to claim that any causal links connect the nonrationalist trends in political theory to the contemporary politics of “post-truth,” but it is heartening to encounter a thoughtfully argued and plausible case against the very concept of post-truth politics.