When we ask whether something exists, we expect a yes or no answer, not a further query about what kind of existence, how much of it, whether we mean existence for you or existence for me, or whether we are asking about some property which it might have. In this book, this simple requirement is defended and pursued into its various and sometimes surprising implications. In the course of this pursuit, such questions arise as ‘Do appearances exist?' ‘Do unknowable things exist?' ‘Do past and future exist?' ‘Does God necessarily exist?' This novel and non-technical approach to important philosophical questions will be of interest to senior students of philosophy and, indeed, to all general readers with philosophical interests.