Calvin Burgess (LMU Munich)
Williamson (2007) argued that if probabilities are regular then certain qualitatively identical events must be assigned different probabilities, which is implausible. His remarks suggest an assumption that chances supervene on qualitative local circumstances and space-time invariant laws. Weintraub (2008) responds that Williamson's events differ in their inclusion relations to each other, or between their times, and this can account for their differences in probability. Haverkamp and Schulz (2011) argued against Weintraub, but inconclusively. However, Weintraub's argument ignores the distinction between qualitative differences and mere matters of time and bare identity. It also ignores the relativity of simultaneity. Furthermore, there are other examples where Weintraub's response simply does not hold. There, the qualitatively identical events are entirely disjoint, as are their times and places.
