Introduction

Note: We are grateful to De Gruyter for the opportunity to compile this compendium, which we hope will offer many a curious reader a good introduction to the subject. At De Gruyter, we are especially thankful to Christoph Schirmer, who found interest in our idea, and Mara Weber, who helped with production. Moreover, we owe thanks to Konrad Vorderobermeier for careful copy editing. We also thank an anonymous reviewer. Of course, our gratitude goes to all the authors who have put so much effort into their contributions.

As Wesley Buckwalter and Justin Sytsma (2016, p. 1) once put it, experimental philosophy (or "x-phi", for short) "is a way of doing philosophy". A way that, in its broadest definition, uses the methods of empirical science - e.?g., from psychology, the social sciences, or experimental economics, to name but a few - to explore philosophical questions from a somewhat new point of view. Following this way is highly contested and one might argue that experimental philosophy, after all, fails to contribute in a significant way to philosophical issues for fundamental reasons. However, for others, us included, x-phi is one of the most exciting developments in contemporary philosophy. And one that is rapidly evolving. Over the last two decades, research in this area has steadily increased, skyrocketed even, one might say. Nowadays, a wide variety of experimental methods - from vignette studies to corpus analyses or eye-tracking measurements - is used to approach an even wider variety of philosophical topics and issues. The rapid growth of x-phi within the last few years may be understood as a growing interest and recognition of the field. However, as the number of contributions to experimental philosophy increases, it becomes increasingly difficult to get an overview of its various topics and branches, especially for the interested novice.

This is where our Compact Compendium of Experimental Philosophy comes in. With the volume at hand, we want to provide - especially for newcomers or researchers unfamiliar with a particular branch of x-phi - a quick introduction and a sound orientation. To this end, the volume is divided into three parts. While the first part takes a look at x-phi as such from a metaphilosophical point of view, the second and third parts focus on specific topics of x-phi. For the sake of organization, we follow the distinction between theoretical and practical philosophy; in Part 2, you will find the philosophical areas that primarily belong to theoretical philosophy, while in Part 3, you will find those that mainly belong to practical philosophy. However, how can this volume provide a brief but substantial introduction to the philosophical areas of, say, experimental metaphysic or experimental political philosophy? For each of these philosophical areas, there are several topics and issues that are debated and experimentally explored. To briefly touch on each topic would result in a rather superficial introduction; to go into each topic in depth would cause the book's scope to sprawl and would undermine the idea of a compact compendium. This is why we have decided to structure the chapters of Parts 2 and 3 in the following way: Each chapter presents a specific core topic that is prototypical of a specific area of experimental philosophy (e.?g., causation as a core topic from experimental metaphysics or the social contract as a core topic from experimental political philosophy). The core topics are the main subjects of the respective chapters. However, each chapter also includes an additional section showing what further topics exist in the area besides the core topic in order to provide a brief overview of the experimental research of this area as a whole.

1 Philosophy of Experimental Philosophy (Part 1)

Now, what awaits you in the following? Part 1 of this volume is concerned with experimental philosophy as such, or with "the philosophy of experimental philosophy". It situates x-phi within the history of Western philosophy (Chapter 1) and shows exemplarily how it lends methods from the social sciences and digital humanities (Chapter 2). Chapters 3 and 4 are dedicated to criticisms of experimental philosophy. This criticism is particularly important because experimental philosophy is once again igniting a dispute about what philosophy is. This is about nothing less than the important question of who we - as philosophers - actually are. And about the question, "what are we doing here anyway?" (as Bauer 2020, par. 15, put it). That's why we consider it important to include these debates here as well. We will leave it at this point; this exciting debate will surely be continued in other places with many passionate voices and interesting perspectives.

Let's take a closer look at the chapters of Part 1. First, Justin Sytsma, Joseph Ulatowski, and Chad Gonnerman (Chapter 1) focus on the History and Philosophy of Experimental Philosophy. They demonstrate that empirical claims and references to empirical observations are not uncommon in the history of Western philosophy. After a general discussion of the relevance of history for experimental philosophy, they highlight important stages from antiquity to the early and late moderns as well as to the present.

Next, Eugen Fischer and Justin Sytsma (Chapter 2) examine Projects and Methods of Experimental Philosophy. They identify a metaphilosophical naturalism as a central new methodological perspective; philosophical questions about certain phenomena are investigated by empirically studying how people think about the phenomena in question. The authors explore the question of how the results of these investigations can contribute to answering philosophical questions and highlight the potential of methods from psycholinguistics and corpus methods from the digital humanities.

Joachim Horvath (Chapter 3) illuminates the role of Intuitions in Experimental Philosophy. X-phi challenges the role of intuitive judgments in philosophical thought experiments by experimentally examining intuitive folk judgments. Horvath discusses two strategies to defend the traditional method of cases against the challenge posed by x-phi, the so-called expertise defense and the mischaracterization objection. The expertise defense assumes that, contrary to expert intuitions, laypeople's intuitions are susceptible to irrelevant factors. Hence, they do not contribute to case judgments in a meaningful way. According to the mischaracterization objection, on the other hand, laypeople's intuitions are irrelevant to the method of cases because philosophers do not judge intuitively but argue for case judgments. Horvath concludes that the expertise defense should be rejected, but he finds arguments supporting the mischaracterization objection and, in doing so, challenges x-phi's challenge to the method of cases.

Theodore Bach (Chapter 4) takes a further look at the Limitations and Criticism of Experimental Philosophy. He distinguishes between the limitations of x-phi, on the one hand, indicating what x-phi cannot do due to conceptual, confirmational, as well as empirical factors, and criticisms of x-phi, on the other hand, containing negative evaluative claims about x-phi's basic idea of using experimental methods to investigate philosophical issues. In doing so, Bach points out synergistic relationships between certain limitations and/or criticisms.

2 Topics from Theoretical Philosophy (Part 2)

Part 2 of our volume deals with experimental philosophical approaches to relevant topics in theoretical philosophy. First, in Experimental Metaphysics, Paul Henne (Chapter 5) explores the core topic of Causation. Henne reviews work on causal judgments based on omissions and normality effects. He further explains how the temporality of actions affects causal judgments in preemption and overdetermination scenarios and discusses problems of the counterfactual account of causation due to cases of double prevention.

James Beebe (Chapter 6) is concerned with Experimental Epistemology, focusing on Knowledge and Gettier Cases. He discusses experimental evidence on the ordinary concept of knowledge and points out differences between laypeople's and philosophers' judgments on Gettier cases due to the distinction between what he calls merely apparent and authentic evidence in the evidential basis of beliefs.

In Experimental Philosophy of Language, Edouard Machery (Chapter 7) provides an overview of the discussion on the semantics of Proper Names and Predicates. To this end, he reviews cross-cultural work on the reference of proper names and examines experimental results on the question of whether laypeople are committed to an internalist or externalist account of the semantics of predicates.

Igor Douven, Shira Elqayam, and Karolina Krzyzanowska (Chapter 8) showcase contributions to the Experimental Philosophy of Logic and Formal Epistemology, focusing on Conditionals. Given that everyday reasoning shows not to be based on the material conditional of...