Ethical collisions are part of collective human life. By ‘ethical collisions’ I mean encounters between individuals and groups whose identities are shaped by conflicting views as to how humans should live their lives, which in turn shape their everyday behavior and practices. I call these ‘ideas of the good life’. Such ideas may be based on cultural traditions, religious beliefs, philosophical positions, political ideologies, or other allegiances. They may be held tacitly rather than explicitly and are connected in complex ways with economic interests, claims to justice, struggles for freedom, and other individual and collective motivations.
 
Historically, ethical collisions have been the cause of deep social unrest, giving rise at times to violent conflicts. Moreover, they continue to be socially divisive. Think of the recent spate of deadly mob attacks in India against cattle traders, beef eaters, and dairy farmers in the name of protecting the sacred cow. Or again, the persistent conflicts in France over women wearing a burkini in public swimming pools or on beaches. Social divisiveness is a serious practical-political problem, for every political order depends for its reproduction on a minimum of social cohesion. In our turbulent times of global migration, with increasing encounters between individuals and groups who hold conflicting ideas of the good life, the challenges are particularly pressing. This is true even for contemporary democracies, where a general, deep-reaching commitment to norms of equality, inclusion, human interconnectedness, and freedom is supposed to provide for social cohesion. For one thing, citizens may interpret these norms very differently, rank them in very different ways, and have an ambivalent attitude towards one or more of them. For another, substantial immigration flows put pressure on commitment to these norms: they may overburden established systems of economic redistribution and social welfare, or decrease already scarce employment opportunities, leading citizens to re-evaluate their commitments to democratic normativity. In addition, they may change the demographics to such an extent that significant numbers of the population no longer share any deep-reaching commitments to democratic normativity.
 
In his book Political Liberalism, John Rawls confronts the problem of ethical collisions squarely. He asks: “How is it possible that deeply opposed though reasonable comprehensive doctrines [in my language, ‘ideas of the good life’] may live together and all affirm the political conception of a constitutional regime?” (Rawls 1996 xviii) Rawls sees the success of liberal constitutionalism as the discovery of the possibility of a reasonably harmonious and stable pluralist society, based on the successful and peaceful practice of toleration. However, as Rainer Forst shows in his book Toleration in Conflict, historically toleration has not only enabled liberal constitutionalism; it has also led to anti-liberal and, more generally, anti-democratic attitudes and practices (Forst 2013). Forst makes a strong case for toleration, but insists on the need to distinguish between permission-based and respect-based versions. Permission-based toleration is hierarchical: it grants minority groups a space within society that is respected and protected, but the sovereign or the majority control what minority groups are allowed to do or not to do. Hence, their citizen status is second class, inferior to that of the majority. By contrast, respect-based toleration is non-hierarchical. It supports a social order based on equal moral respect for citizens, in the sense of respect for their self-reflective, reason-giving agency. In a social order of this kind, laws, ordinances, and public policies are valid when they respect each citizen’s moral agency and prove generally acceptable in public processes of justification guided by norms of reciprocity and generality. Thus, in a social order of this kind, citizens respect one another as moral agents, notwithstanding their very different, and possibly conflicting, views of the good life. They may object to certain practices and behavior, and reject them as ethically unacceptable, but they are prepared to accept them so long as they do not undermine valid laws, ordinances, and public policies.

A significant merit of Forst’s respect-based conception of toleration is that it avoids a certain kind of depoliticization of ideas of the good life, and the behavior and practices to which they give rise. It does not depoliticize, in the sense that it does not make such ideas, behavior, and practices a purely private matter, immunized against regulation by public law. When depoliticized in this sense, practices such as non-consensual sexual intercourse between marriage partners, beating of children by their parents and cruelty to domestic animals are placed beyond the control of public law. Furthermore, they are insulated against interrogation in the media, in art and literature, in educational institutions, and in other agencies that are a vital part of the democratic public sphere.
 
Forst’s conception is not open to this objection. (At least not straightforwardly: I will suggest that even respect-based toleration tends towards this kind of depoliticization.) For Forst, ‘private’ and ‘public’ are dynamic categories: what counts legally as public or private is always contestable, a matter to be determined on a case-to-case basis by way of public practices of justification, which feed into democratic law-making processes. Similarly, the question of which particular ethical practices should be tolerated cannot be answered independently of public practices of justification, which, though always guided by norms of generality and reciprocity, must be responsive to arguments that arise in particular contexts. For this reason, toleration of particular ideas of the good life, and the practices and behavior connected with them, is always contextual: citizens are called upon to tolerate practices they reject, when they do not have rationally justifiable reasons for rejection that could be made general, in the sense of equally acceptable to everyone in their capacity as a moral agent.

In the same vein, what counts as a good reason is something to be determined in public discussion, again with the stipulation that good reasons must meet formal criteria of generality and reciprocity. However, Forst assumes that in contemporary democracies, where there is a culture of political secularism, reasons appealing to religious faith would inevitably fail to meet these criteria (Forst 2017). This may be true empirically, so long as a politically secular culture prevails. But even within contemporary democracies, cultures of secularism are undergoing profound changes, not just due to new demographics, but also to changes in the way religious believers and non-believers understand what it means to embrace secularism. Furthermore, the criteria of generality and reciprocity are not purely empirical, but have a normative moment that pushes them perpetually beyond their factual limits. Forst does not say much about this, but he may well agree. This means that a good reason for legally permitting or prohibiting a certain practice is not simply one whose generalizability or non-generalizability is affirmed democratically by citizens in light of ideas of the good life they hold now and forever. Rather, a ‘good reason’ is a fluid category, always subject to change due to what I call ‘shifts in ethical perception’. By ‘shifts in ethical perception’ I mean changes in ethical self-understanding—changes in our ideas of the good life, and in the behavior and practices connected with them. They have affective, cognitive, and behavioral components, changing our feelings, our thinking, and the concrete ways we live our daily lives. Think of a vegetarian who becomes a committed meat eater or a meat eater who becomes a committed vegetarian following his experiences, direct or mediated, of the mob-riots in India in defense of the sacred cow. Or think of someone who newly adopts the practice of wearing a burkini on public beaches following her experiences, direct or mediated, of the current policies and debates in France; or of a former burkini wearer who now sees that bikini wearing fits better with her own ethical self-understanding. Such changes have complex, contingent causes that relate to the particular psychology and historically situated life-contexts of those in whom they occur. They can arise from individual experiences or from collective ones, and from the interaction between individual and collective experiences. They may be provoked or fostered by public discussions or by experiences independent of any kind of discussion, or by a combination of the two.

What I have just described could be called ‘ethical learning’: the embracing of modified or new ideas of the good life, and corresponding behavior and practices, following events occurring in individual life experiences. Such learning calls for an openness to alien ways of thinking about and living a good life that extends into the very depths of our identities. This kind of openness cannot be taken for granted. It can be actively encouraged, for instance through education, cultural initiatives, political leadership, civil disobedience and other forms of public protest. But toleration works in the opposite direction. It calls for distancing and disengagement from troubling ideas of the good life. As Forst puts it, toleration is a matter of acceptance despite ethical rejection and objection. Certainly, in contexts of intense ethical collision, respect-based toleration may help to establish non-hostile social conditions that allow potentially conflicting parties to live peacefully alongside one another. But we must be alert to its limits and dangers. Toleration does not only suspend mutual learning in the ethical domain, it is hostile to it. Peaceful cohabitation slides easily into privatization, insulating ideas of the good life against public discussion and contestation, which are important sites for ethical learning. In sum, we must see toleration, at best, as a temporary arrangement pending social conditions conducive to mutual ethical learning.