An argument system could be viewed as a pair of a set of argument and a binary attack relation between arguments. The semantics of argumentation rests on the acceptability of arguments and the structure of arguments and their attack relations. While there is a relatively good understanding of the acceptability of arguments, the same can not be said about their structure and attack relations. In...

Anselm’s Ontological Argument fails, but not for any of the various reasons commonly adduced. In particular, its failure has nothing to do with violating deep Kantian principles by treating ‘exists’ as a predicate or making reference to ‘Meinongian’ entities. Its one fatal flaw, so far from being metaphysically deep, is in fact logically shallow, deriving from a subtle scope ambiguity in Anselm...