Thought Experiments. A Phenomenological Account

Recent years have seen a vast increase in the literature on thought experiments. This is not surprising if one acknowledges that thought experiments seem to be an inherent part of our epistemic practices in science as well as in philosophy. Thought experiments are frequently used in classical and post-classical physics, in biology, in mathematics, in applied statistics, in the cognitive sciences, in linguistics, in the study of literature, in economics, in the political sciences or in history. But thought experiments have also shaped the face of modern philosophy, especially in epistemology, in ethics, in the philosophy of mind or in the debate about personal identity. Given this situation, the philosophical analysis of thought experimental reasoning seems to be of utmost importance, both from a metaphilosophical perspective and from the perspective of the philosophy of science. The planned research project "Thought Experiments. A Phenomenological Account" shall shed light on the discussion by trying to develop a particularly phenomenological framework. The basic thesis is that thought experiments confront us with imaginary scenarios in order to highlight previously unrecognized inconsistencies between certain theories, claims or unreflectively accepted intuitions on the one hand and fundamental conceptual commitments on the other. However, the specifically phenomenological aspect of the research project is that the notion of "conceptual commitment" is embedded in the wider context of Husserlian methodology. In particular, the research project will draw upon the Husserlian conceptions of horizontal intentionality and imaginative variation in order to elucidate the relations between thought experimental reasoning and eidetic insight. Although this basic idea of a phenomenological framework shall be applied to both scientific and philosophical thought experiments, the present research proposal concentrates on scientific thought experiments, namely on Galileo`s rejection of the Aristotelian theory of falling bodies. This particular thought experiment serves as a historical example for demonstrating the peculiar character of a phenomenological account on thought experimentation. This example also allows to highlight the differences between a phenomenological approach on the one hand and the accounts of James Robert Brown, John Norton and Tamar Szabo Gendler on the other.

Within the contemporary debate, it is common to refer to the so-called paradox of scientific thought experiments. Briefly put, the paradox consists in the following: Thought experiments are part of core disciplines such as physics and biology. What is more, at least some of these thought experiments seem to provide us with knowledge about the world. But how is this possible? Since they are experiments in thought, thought experiments do not establish cognitive contact with the world. This makes their alleged success puzzling indeed: How can we learn something about the world by merely thinking about it? Different theoretical solutions have been proposed in order to solve this paradox: Some theorists believe that scientific thought experiments allow us to directly see the laws of nature with our minds eye. Others claim that thought experiments are nothing more than chains of inductive or deductive inferences. Still others explain thought experiments by means of a psychological theory according to which the manipulation of mental models allows us to trigger knowledge formations that are not cognitively available otherwise. The aim of this research project was to formulate an alternative account on scientific thought experiments that draws on the rich ressources within the philosophical tradition of (Husserlian) phenomenology.What sets a phenomenological account on scientific thought experiments apart from other approaches is, among other things, its point of departure: Instead of treating thought experiments as explananda that ought to be explained by virtue of a certain theory, phenomenology starts with a careful and metaphysically unbiased description of the kinds of acts that are part of thought experimental reasoning, as well as of their intended objects. This approach allows a phenomenological account on thought experiments to steer clear of the unfruitful dichotomy between rationalism and empiricism.However, a phenomenological take on scientific thought experiments also allows for a more multi-faceted and fine-grained analysis of the different types of thought experiments. As I have shown in detailed descriptions of, for instance, Newtons famous bucket-experiment, the success or failure of thought experiments depends on a number of implicit knowledge formations that are triggered by letting a particular thought experimental setup run. I have tried to analyze these implicit knowledge formulations in the framework of a phenomenological theory of intentionality that does justice to the complexity of, both, human consciousness and the processes that are involved in thought experimental reasoning. Even though my research on this issue is not completed yet, I hope to have already contributed to a better understanding of one of the most fascinating components of scientific methodology.