Julie Schweer

Given that explanation is at the heart of science and considering that computer simulations have become ubiquitous in a multitude of scientific fields, it is important to examine their role in the acquisition of scientific explanations. Even though philosophers of science are increasingly paying attention to the use of computer simulations in explanatory contexts, the concrete contributions that simulations can make to explanations deserve closer philosophical scrutiny. Zooming in on the case of atomistic simulations and starting from a counterfactual account of explanation, we here explore how such simulations can help scientists tackle three relevant challenges in the search for explanations. We argue that atomistic simulations can help access variables at explanatorily relevant levels of description, that they can help track the effects of changes in variables in a highly controlled and fine-tuned way, and that they can allow for a fine-grained account of the relative importance of various difference-makers. Considering a concrete example and illustrating how atomistic simulations are actually used in scientific practice to support explanations, our examination aims to contribute to a more comprehensive and nuanced view of their explanatory power.

Nicht eine Wolke aus Asche und Staub, sondern ein „Schwarm von Daten“ habe 2010 nach dem Ausbruch des isländischen Vulkans Eyjafjallajökull den Flugverkehr zeitweise lahm gelegt, so Frank Schirrmacher (2010) in der FAZ. Die Rede ist hier von den Ergebnissen von Computersimulationen, die bei der Entscheidung über das Aussetzen des Luftfahrtgeschehens maßgeblich waren. Die von Schirrmacher geäußerte Kritik ist eine, die auch in der Wissenschaft und in der Philosophie gegen Simulationen erhoben wird: Dass Computersimulationen eben keine wirklichen Messungen oder Beobachtungen sind.

Explanation is commonly considered one of the central goals of science. Although computer simulations have become an important tool in many scientific areas, various philosophical concerns indicate that their explanatory power requires further scrutiny. We examine a case study in which atomistic simulations have been used to examine the factors responsible for the transport selectivity of certain channel proteins located at cell membranes. By elucidating how precisely atomistic simulations helped scientists draw inferences about the molecular system under investigation, we respond to some concerns regarding their explanatory power. We argue that atomistic simulations can be tools for managing molecular complexity and for systematically assessing how the occurrence of the explanandum is sensitive to a range of factors.