Computing and Informatics

We propose a way to define (and, in a certain extent, even to measure) the phenomenon of emergence which appears in a complex system of interacting agents whose global behaviour can be described by a language and whose components (agents) can also be associated with grammars and languages. The basic idea is to identify the ``linear composition of behaviours'' with ``closure under basic operations'', such as the AFL (Abstract Families of Languages) operations, which are standard in the theory of formal languages.