This paper explores the subject of enterprise-wide information systems in terms of how they support business organizations as living, cognitive human social systems.  It questions whether the autopoietic definition of living systems truly applies to human social systems, and it proposes a formal definition of the human social system, incorporating the notion of the meme.  It further draws on the systemic concepts of the living systems model, the viable systems model, and a cognitive model of the human brain, to suggest a conceptual architecture of enterprise information systems. It incorporates the biological concept of symbiogenesis to provide an evolutionary perspective on how variety is introduced into organizations and selected for successful innovation.  Finally, this paper briefly considers how the current explosion of information technology is driving the evolution of business designs.

Keywords:  information systems, enterprise cognition, autopoiesis, meme, human social system, business design