International Relations Theory

Even as work in the natural sciences has shown the Newtonian understanding of the world to be faulty, Newtonianism still pervades the field of International Relations (IR). Moved by the challenges to Newtonianism emanating from various fields, IR scholars have turned to complexity theory or quantum physics for an alternative onto-epistemological basis on which to build a post-Newtonian IR. This article provides researchers with a map that allows them to not only better see and navigate the differences within both complexity and quantum theory and the IR work that draws from each, but also to recognize the similarities across these bodies of work. Complexity theory highlights and engages systems (biological, social, meteorological, technological, and more) characterized by emergence, self-organization, nonlinearity, unpredictability, openness, and adaptation—systems that are fundamentally different from the self-regulating mechanic systems that comprise the Newtonian world. Complexity-grounded IR research, following complexity research more generally, falls into one of two categories. Through “restricted complexity” approaches, researchers use simulation or modeling to derive knowledge about the dynamics of complex social and political systems and the effect of different kinds of interventions. Researchers who take “general complexity” approaches, by contrast, stress the openness and entwinement of complex systems as well as unpredictability that is not exclusively the result of epistemological limitations; they offer critical re-theorizations of phenomena central to IR while also using qualitative methods to demonstrate how complexity-informed understandings can improve various kinds of practices. “Restricted complexity” seems to have gained the most traction in IR, but overall, complexity has had limited uptake. Quantum physics reveals a world with ineluctable randomness, in which measurement is creative rather than reflective, and where objects shift form and seem to be connected in ways that are strange from a Newtonian perspective. IR research that builds from a quantum base tends to draw from one of two categories of quantum physical interpretation—the “Copenhagen Interpretation” or pan-psychism—though more exist. Unlike the complexity IR community, the quantum IR community is ecumenical; given the deep ongoing debates about quantum mechanics and its meaning, embracing different ways of “quantizing” IR makes sense. Most quantum IR work to date stresses the utility of the conceptual tools that quantum physics provides us to rethink a wide variety of socio-political phenomena and hedges on questions of the nature of reality, even as the major theoretical tracts on quantum social science take strong ontological stances. Developing critiques and alternative positive visions for IR on the basis of either complexity theory or quantum work has been an important first step in enabling a post-Newtonian IR. To advance their agenda, however, the critics of Newtonian IR should start engaging each other and carefully interrogate the relationship between different strands of complexity and quantum theory. There are a number of key points of overlap between the work in the general complexity strand and the Copenhagen Interpretation–inspired philosophy of agential realism, and as of 2022 there exists only one major effort to bring these strands of quantum and complexity together to found a post–Newtonian IR. A coordinated post-Newtonian challenge that brings complexity-grounded IR scholars together with quantum-grounded IR scholars under a common banner may be necessary to wake IR from what Emilian Kavalski calls its “deep Newtonian slumber.” The pay-off, post–Newtonian IR scholars argue, will be a deeper understanding of, as well as more effective and ethical engagement with and in, a non-Newtonian world.

Despite the dominance of development economics in the study of foreign aid and development cooperation since the 1950s, particularly with the emergence of modernization theory, an examination of academic contributions to the larger debates in international relations (IR) reveals something not extensively documented in the scholarly literature. It is that the study of foreign aid and development cooperation is inherently intertwined with IR, constituting an integral component thereof. Understanding the evolution of foreign aid and development cooperation studies, as well as its interaction with IR theories, is essential for deciphering the contemporary theoretical, normative, methodological, ontological, and epistemological challenges faced by the field. Investigating the historical evolution of this field in relation to IR involves analyzing, in parallel, its development alongside shifts in the international order. The historical analysis highlights how foreign aid and development cooperation have been shaped by changing power structures, ideological shifts, and geopolitical events, underscoring its inseparable connection to broader IR dynamics and its theorization. The interconnected nature of these domains demonstrates how prevailing theoretical perspectives influence not only the methods employed but also the identification of underlying forces and the normative principles guiding research, as well as the design of foreign aid and development cooperation policies. Analyzing how epistemological approaches, such as rationalism and reflectivism, have influenced the investigation of narratives and practices within the realms of foreign aid and development cooperation reveals potential elements of theoretical complementation. Beyond mere theoretical differentiation, there are elements that contribute significantly to fostering notions of dialogue, pluralism, and interdisciplinarity within the field of foreign aid and development cooperation studies. The prevailing trend is a movement toward theoretical eclecticism, wherein researchers increasingly draw upon a variety of theoretical frameworks to better grasp the intricate dynamics of foreign aid and development cooperation. This transformation stems from the evolving nature of global challenges and the recognition that a singular theoretical approach may fall short in capturing the multifaceted dimensions of foreign aid and development cooperation. Moreover, it underscores the dynamic and evolving nature of the field, emphasizing the need for interdisciplinary approaches and theoretical flexibility to address the complex issues surrounding foreign aid and the discussion of the concept of development in times of global planetary crisis.

Theory shapes how data is collected and analyzed in at least three ways. Theoretical concepts inform how we collect data because data attempt to capture and reflect those concepts. Theory provides testable hypotheses that direct our research. Theory also helps us draw conclusions from the results of empirical research. Meanwhile, research using quantitative methods seeks to be rigorous and reproducible. Mathematical models develop the logic of a theory carefully, while statistical methods help us judge whether the evidence matches the expectations of our theories. Quantitative scholars tend to specialize in one approach or the other. The interaction of theory and data for them thus concerns how models and statistical analysis draw on and respond to one another. In the abstract, they work together seamlessly to advance scientific understanding. In practice, however, there are many places and ways this abstract process can stumble. These difficulties are not unique to rigorous methods; they confront any attempt to reconcile causal arguments with reality. Rigorous methods help by making the issues clear and forcing us to confront them. Furthermore, these methods do not ensure arguments or empirical judgments are correct; they only make it easier for us to agree among ourselves when they do.

The scientific study of international processes (SSIP) has made substantial progress over the past twenty years, establishing itself as the mainstream research community in the field of international relations (IR) and attracting more and more attention from other disciplines. This was due to the convergence of several revolutions that have taken place in the field, including the data revolution, the formal modeling revolution, the methods revolution, the substantive revolution, and the epistemological revolution. In addition to the dramatic increase in the number of the community of scholars who use scientific logic, systematic methods, and empirical data to study IR, there was a significant improvement in the quality of research. This research has yielded important contributions to our understanding of international processes. Some of these contributions went far beyond the field; they have attracted the attention of policy makers as well as quite a few scholars from other disciplines. Some of the key findings that emerged from this research have become—correctly or incorrectly—a key component of the discourse of political leaders. Growing data availability, increased methodological sophistication, and greater scientific discipline within the profession have converged to open new research frontiers, but important challenges remain, such as the disconnect between theory and empirical tests that exists in many cases, and the almost exclusive reliance on the dyadic level of analysis. It is important to make our understanding of international processes translated into broader policy implications.