 Philosophers often use the notion of a singular proposition. A singular proposition is supposed to be (i) “directly about” an object and (ii) evaluable as true or false. Direct aboutness requires that what the proposition is directly about exists if the proposition exists. If one combines (i) and (ii) with the plausible assumption that the proposition that Superman does not exist is singular and true, one arrives at the conclusion that Superman exists. Similar problems arise for negative modal existential singular propositions such as the proposition that Socrates might not have existed. Williamson 2002 argues on the basis of these problems that everything exists necessarily. Williamson’s modus ponens is Plantinga’s (1983) and Merricks’s 2015 (chapt. 5) modus tollens: singular propositions can exist although the object they are directly about doesn’t.