Grosseteste does not reject this conception of per accidens modalities.  Rather, he introduces another family of modal notions unconnected to considerations of time or change, a family of non-temporal modal notions. And he holds that many true propositions about the future, including those about future free acts, are contingent in the sense of contingency belonging to this family, as indeed also are true propositions regarding God’s knowledge of those acts, past prophecies of them or even statements to the effect that it was the case that the acts would occur.  Ideas along these lines, we may note, were not original to Grosseteste; they are implicit in some of his predecessors, such as Peter Lombard, whom Grosseteste cites. But they, unlike Grosseteste, had not attempted to work out in any detail a theory of modality severing a link with considerations of time and change (the twelfth-century thinker, Peter Abelard, is an exception, but his theory of non-temporal modality, which takes as its central notion that of a thing’s nature, is very different from Grosseteste’s and had little influence). Thinkers after Grosseteste, such as Duns Scotus, developed accounts of non-temporal modality in even more detail that share elements found in Grosseteste’s account and were perhaps influenced by it (see Lewis 1996).