No prediction can distinguish the predicted event in such a way as to discriminate it from any of the other possible events that could fall under the same set of measurements…. The statement which expresses our prediction is never capable of identifying without ambiguity one and only one event whose occurrence would satisfy the prediction, for a description can do no more than specify a class of closely similar events, whose differences lie beneath the threshold of discrimination#Quoted in Gerald O'Driscoll & Mario Rizzo, The Economics of Time and Ignorance (1985)