Abstract
Lange (2017) has done groundbreaking work on the explanatory role of constraints. However, besides having an explanatory role, some constraints, such as perspectival ones, can also have a pragmatic role in explanation. In this talk, I develop an account of perspectival constraints based on erotetic reasoning. Erotetic reasoning relies on the inferential patterns which determine both the questions and the space of possible answers to them. According to this view, questions can be conclusions in arguments that show how a question arises from certain contexts (Hintikka 1981; Winiewski 1996). For example, we can start from a set of propositions and derive questions based on the syntax and semantics of those statements: (1) If the city of Königsberg has a layout of landmasses and bridges such that they form a connected graph with a topological property p, then Königsberg cannot be traversed by crossing each bridge exactly once (an Eulerian path is impossible). (2) Königsberg has a layout of landmasses and bridges with a topological property p’. (3) Is an Eulerian path possible in the city of Königsberg? In this example, the erotetic argument starts with a statement about what it is for an arrangement to have a certain topological property p. From this, a relevant counterfactual that grounds an explanation could be derived: Had Königsberg’s layout had a topological property p, an Eulerian path in the city would have been possible. The inferential pattern in this toy example makes it intelligible why appealing to topological properties counts as an explanation of why the Eulerian path is impossible, but also why appealing to actual walking through the city does not (Lange 2018; Kostic and Khalifa 2021). To show how this analysis can be generalized from toy examples to actual explanations in science, I discuss an account of topological explanation (Kostic 2020) which outlines perspectival constraints for using the counterfactual information in two explanatory modes, i.e., a horizontal or a vertical explanatory mode. In the horizontal mode counterfactual dependency holds between properties at the same level, whereas in the vertical mode it holds between properties at different levels. The horizontal and vertical modes emerge from different question-asking contexts, thus by using erotetic reasoning I show how perspectival constraints enhance intelligibility of explanation, rather than relativizing it.