Empty name

In metaphysics and the philosophy of language, an empty name is a proper name that has no referent.
The problem of empty names is that empty names have a meaning that it seems they should not have. The name "Pegasus" is empty; there is nothing to which it refers. Yet, though there is no Pegasus, we know what the sentence "Pegasus has two wings" means. We can even understand the sentence "There is no such thing as Pegasus." But, what can the meaning of a proper name be, except the object to which it refers?
Overview.
There are three broad ways which philosophers have tried to approach this problem.
Some philosophers, such as Alexius Meinong have argued that there are two senses of the verb "exists", exemplified by the sentence "there are things that do not exist". The first, signified by "there are", is the so-called "wide sense", including Pegasus, the golden mountain, the round square, and so on. The second, signified by "exist" is the so-called "narrow sense", encompassing only things that are real or existent. The difficulty with this "two sense" theory is that there is no strong evidence that there really are two such distinct senses of the verb "to be".
Fictional entities.
Some philosophers employ the related concepts of "fictional entities" (such as Sherlock Holmes) who are deliberate inventions, and of "mythical entities" (such as Vulcan) that result from accidental mistakes. Such entities appear to be employed in many different contexts: