The Noumenal Republic: Critical Constructivism After Kant, by Rainer Forst Cambridge: Polity Press, 2024, <scp>ISBN</scp>‐13: 978‐1‐5095‐6228‐8

There are certain anchor-points in Rainer Forst's thought, concepts which he has taken on from the traditions of moral and political philosophy and developed in his own way: the right to justification, noumenal power, and critical constructivism.These concepts recur throughout this collection of essays, first published in German in 2021, although most of the chapters appeared originally in English.Together they supply the tools for Forst's broadly Kantian-Rawlsian philosophical project, illuminated by Frankfurt School critical theory.The influence of the major thinkers who have supplied the materials for Forst's approach, above all Kant, Rawls, Habermas, and Honneth is clear, but this collection also makes room for his exchanges with key contemporaries.Different essays work through discussions with Amy Allen on progress and universalism, Philip Pettit on republicanism and non-domination, Thomas Scanlon on contractualism, reasons and justification, and Habermas (both a progenitor and a partner in dialogue) on secular reason and the autonomy of morality.Theorists who are not the focus of a single essay, such as Onora O'Neill, Andrea Sangiovanni, and Seyla Benhabib, are referenced throughout, as interlocutors with (and against) whom Forst has developed his philosophical position.The first part of the book is the most "applied," the closest to contemporary social and political struggles, and consists of a series of essays on what Forst calls "normatively dependent concepts" (51-2): alienation, solidarity, progress, democratic regression, and social cohesion.The second part is made up of analyses of more abstract issues in political philosophy: realism, human rights, transnational justice, structural domination, and republicanism.Finally, the third part brings together Forst's engagements with and critiques of particular thinkers and positions: Rawlsian political liberalism and justice as fairness, luck egalitarianism, Scanlon's contractualism, and Habermas' genealogy of religious belief and philosophical reason.Throughout, Forst deploys the central concepts of his philosophical position to re-evaluate, interpret, and critique the subjects of his essays.The core of this position, so far as this collection goes, is the concept of noumenal power.Forst takes up Kant's term and uses it to refer to the human ability to transcend our immediate, phenomenal reality, to think beyond the given world around usincluding, crucially, the norms, practices, and institutions of our society.Humans are noumenal beings to the extent that we can transcend this facticity, and ask what justifies it, what valid justification there are for these norms, practices, and institutions.Noumenal power, then, is the power that results from making and critiquing justifications from this transcending stancethe power one agent has to steer the behaviour of another "from the inside," by offering them acceptable justifications for a course of action.For Forst, "the real site of the exercise of power is the cognitive realm, that is, the realm of justifications, since A needs to be able to effect and change the realm of motivational reasons for B." All real power is a matter of persuasion, of motivating the other through giving justifications, although these need not be good justifications.They can include "a good speech, a