 The practice of thought experiments is not an invention of philosophy and modern science. On the other hand, the view that the Pre-Socratics “invented thought experimentation as a cognitive procedure and practiced it with great dedication and versatility” (Rescher 2005, p. 2) might be a stretch. With such a claim one risks underestimating the entanglement of concepts and corresponding reality. It is probably much more correct to say something like the following: “There is no ancient Greek term corresponding to what we nowadays refer to as a thought experiment, and presumably ancient philosophers did not have our modern notion of a thought experiment. But there is no doubt that they did use thought experiments. In fact, they often employed them in ways similar to those of contemporary philosophers, that is, both for defending their own theories as well as for refuting the theories of their opponents.”(Ierodiakonou 2018, p. 31; see also Becker 2018; Diamond 2002, pp. 229–232; Fuhrer 2009; Glas 1999; Ierodiakonou 2005; Ierodiakonou and Roux (eds.) 2011; Irvine 1991; Rescher 1991 and 2005, pp. 61–72). The situation is similar with respect to medieval natural philosophy, although there are further nuances to be considered (see King 1991). According to Edward Grant, during the late Middle Ages “the imagination became a formidable instrument in natural philosophy and theology in ways that would have astonished ancient Greek natural philosophers, especially Aristotle” (Grant 2007, p. 201). But this doesn’t mean that we have reason to think of Aristotle as an opponent of the conduct of thought experiments. On the contrary, “Aristotle uses thought experiments for argumentative persuasion and in places where, due to the obscure nature of the subject matter or the counterintuitive nature of the thesis they are meant to support, insight cannot be readily communicated by appeal to observational facts” (Corcilius 2018, p. 73). With a few exceptions that involved problems of motion, “the scholastics” made no meaningful effort to transform their hypothetical conclusions into specific knowledge about the physical world. They did, however, assume that although these hypothetical conclusions were naturally impossible, God could produce them supernaturally if he wished. Special attention received also a class of medieval thought experiments that does not rely on counterfactuals but also depends on theological assumptions to study matters non-theological, namely those thought experiments involving angels, whose existence were affirmed at that time (see Perler 2008). Angels are gone by now (see Clark 1992), but not thought experiments. While most thought experiments involving angels have Christianity as their context, there is evidence of the practice of thought experiments also in the context of Islam and Judaism (see McGinnis 2018; Fisch 2019). In fact, the case has been made “that Ibn Sina is the first philosopher in the Aristotelian tradition, and thus perhaps the first in Western philosophy overall, to try to identify the psychological processes that go into postulating a hypothetical scenario. Ibn Sina also exhibits an interest in accounting for why, and to what extent, such psychological acts are thought to carry weight in our study of nature” (Kukkonen 2014, p. 434).