Publication 891

This paper describes the basic features of the theories of complexity and reflexivity, their early history, their evolution, and reactions to date. Although complexity is a major change from previous modeling methods, it does not violate any informal fallacies or any assumptions underlying the philosophy of science. Reflexivity does. Accepting reflexivity as a legitimate movement in science will require an expansion of the conception of science which still prevails in most fields. A shift from Science One to Science Two is now being discussed. Relevance: The arguments refer to Ashby’s and von Foerster’s work in second-order cybernetics.