Engaging with a mundane topic like the softness of international law may certainly look surprising to the readership of a journal known for its avowed and constant quest for an intellectually and conceptually rigorous ‘off-Broadway’ scholarship. Why would a journal that tries to establish itself as a leading alternative voice in the field replay a comedy so often staged in mainstream scholarship? It is with the full awareness of such an anticipated feeling of déjà vu that the editors of the Leiden Journal of International Law have decided to open the ensuing pages to an oft-debated topic with the ambition of evaluating the possibility of transcending the traditional pitched battle between opponents and advocates of soft law. It is well known that, after the juvenile success of the conceptFootnote ¹ and its embrace by a great number of international scholars, soft law became the object of severe criticisms, resulting in a chasm in the international legal scholarship. Indeed, the debate about soft law came to literally split authors into two camps, firmly pitted against one another. On the one hand, there are the advocates of the notion for whom the binary nature of law is incapable of explaining the complexity of the international exercise of public authority in a pluralized worldFootnote ² or who see soft law as an instrument of (programming of the) development of hard law.Footnote ³ These apostles of the notion of soft law are opposed by those who see the notion as redundant because it turns into either hard law or not law at all,Footnote ⁴ it is self-serving for the profession,Footnote ⁵ it is dangerously deformalizing our instruments of law ascertainment,Footnote ⁶ or it is weakening the general authority of law.Footnote ⁷ The fierce character of that confrontation originates in soft law's being intrinsically intertwined with one's core and inner understanding of (international) law, thereby making these discrepancies seem irreconcilable.

It is against the backdrop of these deeply entrenched and seemingly incompatible positions that the following symposium seeks to ignite a reflection about the possibilities of thinking about the softness of international law beyond this classical divide. To do so, the stage is opened to two scholars known for their work on the concept of international law and the pluralization of norm-making processes, Jaye Ellis and Matthias Goldmann. Going down different routes, both authors, in their own refreshing ways, attempt to envisage a future for the concept of soft law in a manner alien to above-mentioned confrontational views from which they distance themselves. Unsurprisingly, their shared default position is that soft law is a reality and instrument of contemporary governance that cannot be wished away. It is a reality, for one thing, in terms of its effects on hard law, as many scholars on both sides of the figural fences would argue. However, both Ellis and Goldmann are dissatisfied with such a narrow focus and portrayal of soft law's indirect importance to the legal process as merely lex ferenda or the ‘avant-garde of legalization’ (Goldmann). Arguably, such a conceptualization ultimately renders ‘soft law’ an oxymoron and reifies the categorical distinction between law and non-law without really accounting for soft law as a recurrent (legal) practice in contemporary international society. In this regard, Goldmann identifies calls for its elimination as a fight against the windmills and dismisses demonization of soft law as futile.

In their exploration of possible futures for the concept of soft law, both authors engage with the criticisms that soft law is a threat to international law proper, because of the dangers of relativism, politicization, and instrumentalization of international law, as well as reducing its effectiveness and coherency because of a proliferation of not necessarily compatible norms. Contrary to these problematizations, both authors seek to overcome the confrontational cleavages by arguing that soft law in fact could also be seen as a solution to acknowledged weaknesses of the traditional international legal order. In this regard Ellis points out that ‘[t]he potential dangers posed by soft law depend on one's approach to defining it’. This means that defining soft law is a prudential question itself, as Goldmann argues, that depends on the context in which one seeks to define international law. And definitions of soft law indeed rather abound and are heterogeneous. Whereas soft law seems to be everywhere, there are many different usages of the term – or should we maybe turn that logic around?

Definitions of soft law often refer to a variety of characteristics, including lack of precision, open-endedness, lack of enforceability, as well as the type of actors that engage in norm generation. Ultimately, these features link to the distinction between law and non-law, which both articles to a certain extent seek to deconstruct. That is to say, rather than fighting or demonizing soft law, both articles seek to make sense of soft law as a ubiquitous practice within contemporary international governance, which calls for a reconceptualization of the boundaries between law and non-law. By discussing different schools of thought in legal theory, they both investigate possible avenues to open up the agenda to include alternative modes of law-making without doing away with the distinctive nature of law altogether. In this process, both authors engage in a conceptual excursus: if soft law is indeed an increasingly popular instrument of law-making after the end of the Second World War, how is it so and what kind of law is it?

Goldmann's straightforward take on the first part of the question is that soft law is law, as it functions like so-called hard law. It does so by operating through formalized decision-making procedures, as well as via its so-called social effects: not only is it often recognized as binding law by parties involved, even if, strictly speaking, it does not qualify as such, it also turns out to be rather effective in constraining state behaviour. In turn, much hard law in fact works like soft law. That is to say, whereas there remain important formal differences (e.g., with regard to state responsibility and the option of going to court), in practice, binding international law is often enforced via exactly the kind of peer-review procedures that are typical of most soft law. Hence, Goldmann argues for an expansion of the concept of law in order to account for the variety of legal and non-legal instruments that are used in contemporary governance. For him, it is notably Günther's deliberative approach of law as a meta-language and ‘universal code of legality’ that can incorporate a sophisticated concept of soft law on its own account, without compromising legal certainty, and maintaining the distinction between legitimacy and validity.

Ellis, on the other hand, takes a more formalist approach to law, and investigates how to redefine the rules of recognition in order to include various heterogeneous practices of law-making in contemporary international society. While sharing the agenda of broadening the concept of law to include its soft variants, the focus of her article differs from Goldmann's by addressing a different aspect of soft law. Rather than the instruments of governance, she is mainly concerned with the role of non-state actors in the creation and implementation of legal regimes. In this context, she is looking for frameworks that can incorporate their role not only as norm entrepreneurs (which, in the current literature, again narrows the scope of soft law as lex ferenda),Footnote ⁸ but the importance of non-state actors as legal norm producers. In other words, she seeks to reconceptualize the rules of recognition beyond their traditional statist focus in order to account for the jurisgenerative capacity of non-state actors. Engaging with Fuller, Kingsbury, and Teubner, she finds the latter's autopoietic theory of global law without the state as most promising to incorporate non-state actors as norm generators within contemporary international governance.

In a sense, one could identify ‘soft law’ as an empty signifier, which refers to a ‘fairly eclectic body of principles, rules, documents, statements, and various forms of communication’ (Ellis). This could be grist to the mill of its critics and render it useless as a scholarly, let alone legal, concept. However, as a ubiquitous practice, the concept of soft law could also be one ‘which both scholars and practitioners ignore at their peril’ (Ellis). This is why this symposium endeavours to further our understanding of the theory and practice of soft law through a critical engagement with a variety of perspectives on the merits and threats of soft law.

The divergences between Goldmann and Ellis regarding the usefulness of the concept of soft law are more specifically laid bare in the replies that they address to each other in two separate shorter pieces. It is hoped that the readers will find useful tools in these engagements to rejuvenate their reflection about soft law as well as the concept of international law as a whole. Whether that suffices to answer positively the headline question of this short introduction remains to be seen. Yet, what matters is only that we allow the debate on such a foundational topic to continue – here, on the new electronic debate platform of our journal designed in collaboration with OpinioJuris.org, or anywhere else. And, as this debate starts to unfold in the following pages, we hope that the feeling of it having been experienced before will, like most déjà vu, quickly be supplanted by the idea of an unfolding and continuing exercise, in this case, one highly conducive to an international legal scholarship in constant need of critical self-reflection about the fundamentals of its object(s) of study.