Wider Still and Wider... Resetting the Bounds of Logic
Johan van Benthem

Abstract:
Modern logic is often defined in terms of specific formal languages, rules, 
and calculi. Such architectural decisions about a field form a pervasive 
implicit definition which determines professional practice -- through the 
structure of textbooks, as well as the research agenda that determines 
'interest', and hence acceptance and academic status. Such a practice may 
come to contain a lot of historical accident, or force of habit. Therefore, 
it seems worth thinking about the defining agenda of a field once in a while.
In this brief essay, we explore alternative views of logic, locating the 
nature of the field in more abstract themes, concerns and attitudes. The new 
definition does not remove the need for the old agenda, but we advocate a 
shift in emphasis, toward greater generality and range of application. The 
outcome is a conception of logic as a broad methodological stance, looking 
for invariants in (information) structures and processes.