The unwanted necessity objection. Consider a sentence like ‘Aristotle taught Alexander the Great’. This seems to be a contingent claim—one that is true but matters could have gone otherwise. Aristotle could have decided it was immoral to take the position, or Phillip of Macedonia could have decided that Aristotle was not the best tutor for his young Alexander. We can imagine numerous possible worlds in which the sentence turns out to be false (unlike necessary claims like ‘5+7=12’ which appear to be true in every possible world). But now consider this sentence with the description unpacked. We get something like ‘The pupil of Plato and teacher of Alexander the Great taught Alexander the Great’, and it seems that this would have to be true in every world in which someone satisfies the relevant description. The problem is that the Russellian analysis seems to turn a contingent proposition into a necessary proposition.