abstract: One activity for which philosophers are perhaps best known is having disputes with one another. Some non-philosophers, and increasingly many philosophers, believe that a number of these disputes are silly or misguided in some way. Call such silly or misguided disputes defective disputes. When is a dispute defective? What kinds of defective disputes are there? How are these different kinds of defective disputes different from one another? What does it mean to call a dispute 'merely verbal'? These questions come up for consideration in Part One of this manuscript. In Part Two I examine whether certain disputes in ontology and over the nature of possible worlds are defective in any of the ways described in Part One. I focus mainly on the question of whether these disputes are merely verbal disputes, though I examine whether they are defective in any other ways. I conclude that neither dispute is defective in any of the senses that I make clear in Part One. Moreover, I conclude that even some defective philosophical disputes can be worth consideration under certain circumstances. / Dissertation/Thesis / Ph.D. Philosophy 2011