   When Brentano reflected on the “quasi-relational” nature of the intentionality of thoughts about things that need not exist, he wrote that if one “is denying something, the existence of the object is precisely what is excluded whenever [one’s] denial is correct”. He thus assumed that one can correctly and coherently deny the existence of things that do not exist. To show that one can do so, however, is no easy task. The version of the puzzle that  exercised both Alexius Meinong (a disciple of Brentano’s) and Bertrand Russell at the turn of the twentieth century is the puzzle of true negative existential beliefs.  How can a person correctly believe that Pegasus does not exist? For a person to correctly believe that Pegasus does not exist, she must have a belief whose content is the same as the content expressed by a true utterance of sentence (7).