Expectation-driven interaction: a model based on Luhmann's contingency   approach
  We introduce an agent-based model of interaction, drawing on the contingency approach from Luhmann's theory of social systems. The agent interactions are defined by the exchange of distinct messages. Message selection is based on the history of the interaction and developed within the confines of the problem of double contingency. We examine interaction strategies in the light of the message-exchange description using analytical and computational methods. 
M. J. Barber, Ph. Blanchard, E. Buchinger, B. Cessac, L. Streit