Abstract
‘What is Life’ and ‘What is Mind’ are simple questions lacking simple answers; there seems an unbridgeable gap from the lifeless, mindless world of physics, perhaps prompting appeals to the supernatural or to ‘Ghosts in the Machine’. Artificial Life researchers have to acknowledge such basic philosophical issues at the core of their studies; but they should reject the notion that living, mindful beings are supernatural. Following Ryle and Wittgenstein we argue that the simple questions are too often made nonsense through category errors, confusion between different levels of description. We consider the role of the observer, and the opposition between objectivity and subjectivity. The sciences of life and the mind are particularly prone to confusions about the roles of observers. We highlight the practical consequences for Alife research. Such category errors undermine the rationale for large bodies of this research. We discuss how to identify these suspect assumptions and how Alife research can avoid these traps.