 Consider our two competing theories of space-time \(T_1\) and \(T_2\) again. Are \(T_1\) and \(T_2\) descriptively equivalent? At the stroke of midnight Cinderella’s carriage changes into a pumpkin—it is a carriage up to midnight, a pumpkin thereafter. According to the region-based theory \(T_2\) which takes temporal intervals as its primitives, that’s all there is to it. But if there are temporal points, instants, as \(T_1\) affirms, there is a further issue left undecided by this story—viz, at the moment of midnight is the carriage still a carriage or is it a pumpkin?