 There is another dimension to the empiricism of this period, which is a new emphasis on experience as a means of discovering causal relations. Any Aristotelian, of course, would have agreed that we know of causal relations by means of experience. But what we find in the work of Scotus and Ockham is a particular focus on this idea, coupled with descriptions of how one may isolate particular causes. Historians have long associated this with a renewed emphasis on God’s absolute power and the idea that the order of the world depends entirely on his will, which makes that order radically contingent and discoverable only a posteriori (Foster 1934: 464–65; Henry 2009: 88). It is, however, difficult to find a contemporary expression of this idea and it has recently been contested (Harrison 2002: 63–64). Nor should one overstate the degree of novelty in the thought of Scotus and Ockham. Grosseteste had already outlined the idea of a controlled experiment (Lewis 2013: sect. 11), noting that we can come to know that scammony (convulvulus scammonia) purges red bile by administering it “after all other causes purging red bile have been isolated and excluded” (Grosseteste In APo. 1.15; Crombie 1953: 74).  It is true, however, that more detailed accounts of how to isolate causal relations are found only in the late thirteenth and fourteenth centuries. Scotus outlined several such methods (Vos 2006: 312–19), all of which involved separating out possible causes and testing them by seeing in which cases the effect follows. At one point, for example, Scotus writes: 