I describes four kinds of knowledge and associate each with distinctive projects. What we generally refer to as positivist IR aspires to what Aristotle calls episteme: scientific knowledge that can be expressed mathematically. Interpretivist approaches aspire to phroēesis, which is best understood as practical knowledge that helps us cope with the world. This distinction cuts across paradigms and is a far more fundamental division.

I build on Max Weber's belief that theories had to be rational (internally consistent) and were only a starting point for understanding real-world behavior, which, even if rational, could understand rationality in different ways as a function of the values people sought to maximize.

I explore different understandings of cause, the extent to which it is a feature of the world or an artifact of our imagination, and the consequences for knowledge that flows from these different assumptions.

Verification and falsification are standard techniques for the evaluation of truth claims. Both are problematic because they rest on shifting understandings of these concepts and their operationalization. Science as a practice offers an alternative and more sophisticated approach to assessment.

The chapter presents a further elaboration of science as a practice, and a critical evaluation of interpretivist approaches to knowledge claims.

I make the case that researchers should understand epistemology and its implications for their work. Provides an overvierw of subsequent chapters.

The chapter describes the assumptions and goals of large n statistical studies and evaluates the extent to which they generate knowledge about international relations.

Interpretivism is a bottom-up approach to knowledge that starts with actors and the reasons they have for behaving as they do. I explore the problems of determining actors' motives and goals and the need for intrpretivism to develop means of studying the aggregation of actor behavior, which is what produces most outcomes.

In this book, I posed three set of questions about each epistemology: how it defines knowledge, how it seeks it, and how its adherents claim to have found it. I have stressed the differences between positivism and interpretivism, but there is also considerable variation within them, variation that should encourage dialogue not only within but also across epistemologies. I discuss some of the forms this dialogue might take and the ways in which researchers in each tradition can learn.

I describe the theoretical assumptions of rational models and assess -- largely negatively -- their ability to produce knowledge relevant to international relations.

Practice theory seeks to explain the relationship between human action by reasoning that most behavior is socially determined and best studied through practices and the institutions they represent and instantiate. Practice theory conceives of behavior as patterned deeds in socially organized contexts. I provide an overview of the practice turn literature. I discuss different understandings of practice, the mechanism of habit, which is closely associated with them, and whether practice theory can be considered causal.

Counterfactuals are central to positivist and interpretivist claims to knowledge. They are used to evaluate propositions, theories, and causal narratives and also to imagine them. In different ways, the failure to consider counterfactual claims or deploy counterfactual arguments weakens claims to knowledge in both research traditions.