Eco-grammar systems: a grammatical framework for studying lifelike interactions.

A formal framework for studying systems made up of a community of agents and their environment is proposed. The suggested model, technically based on the theory of formal grammars and called an eco-grammar system, captures some common features of ecological, economic, social, and collective robotic systems. The article contains an informal presentation as well as the formal definition of the model, presents some properties of variants of eco-grammar systems, and discusses the emergence of important lifelike features such as birth and death. Emphasis is put on results with relevance for artificial life. Some recent developments are also briefly reported.