In the opening essay launching the journal International Theory (IT), the editors Duncan Snidal and Alexander Wendt lamented that while there is a plethora of theory in the study of international relations (IR), ‘different theoretical communities are not engaging each other in ways that could be mutually productive (Wendt and Snidal Reference Snidal and Wendt2009)’. It was in precisely the same spirit of the creators of IT ‘to foster such a dialog’ among the scholarly fields of International Political Theory (IPT) and IR (among others) that I embarked upon a project to try to explore the connections between the empirical study of global norms and their normative evaluation, to break down the ‘silos’ that both I and the editors of IT have witnessed as all too common between normative and positive IR. I am thus doubly grateful – simply for the journal and its mission, and also then for the more pointed opportunity to put my edited volume, Moral Limit and Possibility in World Politics (hereafter ‘Moral Limit’) to work for just what I had hoped it would be – a platform to actually engage in precisely that dialogue.

Also very much in that spirit, I wish to keep this introduction brief, to allow full space for that dialogue to unfold rather than reprising what has already been written in the book or engaging in further monologue. So in this introduction I will simply say a few words about the communities I had hoped to engage with this work, and to what ends. Moral Limit is hardly the first or only kind of attempt to integrate the normative and the positive in the study of IR, and indeed even since its publication I am heartened to see more examples of explicit simultaneous treatments of the two that integrate and/or analyze how they relate to one another.Footnote ¹ It should be said that as a result of the contributions to and reviews of this forum, I am even more mindful than ever of the dangers of invoking the dichotomies – prescriptive/explanatory, empirical/normative, positive and prescriptive IR, etc. – upon which key issues animating the book were premised. Yet if in invoking these terms we are alert to their utility in analyzing different kinds of questions scholars seek to answer and ways of answering them, rather than taking them to signal assigned irreconcilable epistemological and ontological positions that close off debate, most of us can recognize that there are different aims and contributions of scholarship and that there can be value in cross-fertilization to see what insights each might lend the other.

The aim of Moral Limit was not to reinvent any normative wheels nor unduly categorize scholars, though in observing broad tendencies no doubt the nuances and complexities of some scholars are insufficiently attended to, and the contributions of far too many scholars simply overlooked. Yet having those errors and omissions pointed out is a necessary part of the learning process and I am grateful for the correctives I have received along the way including from the contributors to this forum and from its very thoughtful reviewers who have most helpfully engaged with these issues. If those transgressions can be forgiven, then, Moral Limit sought to enjoin a fairly specific set of conversations that have grown out of one particular research trajectory known as constructivism in IR, but which have broad implications for some of the big questions that animate a wide range of scholars of IR including those issues of particular interest to International Theory. The major premise of the book is that explanatory research programmes that have shown how moral norms arise and have an impact on world politics are well-placed to help us answer the ethical question of ‘what we should do’ when faced with moral opportunities and dilemmas in global affairs. In particular, since social constructivist analyses of the development and effects of moral norms entail theoretical and empirical claims about the conditions of possibility and limits of moral change in world politics, that agenda should provide insightful leverage on the prescriptive or ethical question of ‘what ought we to do?’ At least, insofar as one accepts that a responsible answer to the question of ‘what is the right thing to do’? cannot depend solely on an unrealizable ideal (itself of course a claim of no small philosophical debate that the book engages since we want to know what is unrealizable). The corollary of this is the book's contention that ethical prescriptions cannot completely eschew their own empirical assumptions even as they rarely develop them as systematically as does much scholarship that is self-consciously empirical; on the other hand, constructivism in the main has not to date itself developed the normative basis that would allow it to claim that the influence of various global norms do in fact constitute moral ‘progress’.

Thus, one way the book sought to spark conversation was to pose an internal challenge to constructivism to speak to normative IR theory and practical ethics, something it needed to do ultimately to substantiate its claims of moral progress. Another was to pose questions of other approaches as to how they might meet the challenge of making calls about moral limits and possibilities from their perspectives and how empirical work on norms might serve as an aid to normative evaluation, particularly with respect to questions like charges of idealism, co-optation, and hypocrisy. At one end, it sought to challenge sceptical approaches in the field: how do they justify that scepticism in the face of evidence by scholars studying norms that there is more moral change (such as humanitarianism) in world politics than the ontology of scepticism would seem to allow? To engage in that debate, however, ultimately requires that one establish normatively just what one means by progressive moral change. This is because one could object to putative findings of moral progress not just on empirical grounds – for example, debates that the traditional slave trade was brought to an end by economic interests rather than moral entrepreneurship – but also normative grounds – that is, arguments that ‘advances’ in international criminal law or humanitarian intervention are not examples of moral progress because they are undesirable encroachments on communal self-determination, or because they disrupt stability as Snyder and Vinjamuri contend in their work and response in this forum. Thus, I also sought to push constructivist scholars themselves to more explicitly consider the ethical implications of their findings. This brings the empirical study of moral norms into more direct conversation with typical undertakings of IPT to see what it can contribute to more full-blown normative theories that often hinge importantly in some respect upon assumptions about how the moral world works or at least how it might possibly unfold. It also brings the study of ethics into engagement with critical theory in IR, raising issues of power and co-optation, which I turned into a question for such approaches: namely, upon what basis exactly rests the frequent critical charge that otherwise purportedly progressive developments are better seen as unduly co-opted, implying as it does that more was empirically possible?

As with all such endeavors, some among the various communities may see such incursions more as an invasion than invitation, or at best a fanciful quest off disciplinary paths that have been well-worn for good reason. I am grateful for four generous scholars who were willing to at least temporarily humor me and entertain the possibility that these exploratory journeys could prove worthwhile enough to respond with their own considered reactions. Their engagements span a rich gamut of perspectives across empirical IR research, positive IR theory, critical theory, and IPT. While numerous issues are engaged, the contributions to the forum principally revolve around the following themes: (1) whether a division of labor between normative and empirical theory can or should be overcome, which in turn presupposes notions of (2) just what constitutes normative and empirical IR as such; and (3) the ethics of constructivism itself, including what if anything is distinctive about how constructivism might respond to the question of ‘how we should act’. Along with the terribly insightful remarks of the reviewers, these engagements in my mind already make the project a successful one in generating just the kind of rich dialogue it hoped to animate on the pointed question of how we know moral limits in world politics. The extent to which this constitutes even modest intellectual progress I now leave to the other contributors to this forum and its readers.