For the case of imprecise probabilities, however, the situation looks bleak. No real valued scoring rule for imprecise probabilities can have the desirable property of being strictly proper (Seidenfeld, Schervish, and Kadane 2012). Schoenfield (2017) presents a simple version of the result. Since strict propriety is a desirable property of a scoring rule (Bröcker and Smith 2007; Joyce 2009; Pettigrew 2011), this failing is serious. So further work is needed to develop a well-grounded theory of how to assess imprecise probabilities. Mayo-Wilson and Wheeler (2016) provide a neater version of the proof, and offer a property weaker than strict propriety that an imprecise probability scoring rule can satisfy. Carr (2015) and Konek (forthcoming) both present positive suggestions for moving forward with imprecise scoring rules. Levinstein (forthcoming) suggests that the problem really only arises for determinately imprecise credences, but not for indeterminate credence.