In the Preface to Principia Ethica G. E. Moore pointed out that many intractable philosophical controversies spring from a failure to notice that the disputants may be addressing themselves to different questions. The authors' conclusions, however, lend only limited support to the common view that it is in 'linguistic confusions' that metaphysics originates. The three remaining ways of looking at ontology which have been considered in this book cannot be accounted for either by reference to Tillich's conviction that there is a close connection between the religious quest and the ontological question or by pointing to the linguistic confusions of which Tillich may sometimes be justly accused. As Tillich himself believed, the ontological cast of his system is not incidental to the system: to object to its ontological cast is to object to the system.