On defining life, and the very notion of living systems
C. Emmeche (1993): "Is life as a multiverse phenomenon?", pp.553-568 in: Christopher G. Langton, ed.: Artificial Life III (= Santa Fe Institute Studies in the Sciences of Complexity, Proceedings Volume XVII), Addison-Wesley Publishing Company, Reading, Massachusetts.
Claus Emmeche (2004): "A-life, organism and body: The semiotics of emergent levels", pp. 117-124 in: Mark Bedeau, Phil Husbands, Tim Hutton, Sanjev Kumar & Hideaki Suzuki (eds.): Workshop and Tutorial Proceedings. Ninth International Conference on the Simulation and Synthesis of Living Systems (Alife IX), Boston Massachusetts, September 12th, 2004. [pdf file (76 K)]