Crash-proof syntax and filters

This article argues that even when it turns out to be possible to develop a crash-proof syntax that only generates well-formed objects that satisfy the interface conditions, filters on the output of the computational system will remain an essential ingredient of the theory of syntax. This does not necessarily imply, however, that the more general and modest aim of the crash-proof syntax project to limit the output of the derivational system to “objects that are well-formed and satisfy conditions imposed by the interface systems” should be dismissed as irrelevant.