Philosophical issues in the search for extraterrestrial life and intelligence

In the search for extraterrestrial life and intelligence, it is essential to clarify what is to be meant by ‘life’ and ‘intelligence’. I first analyse what it means to ‘define’ these words. I will show that some philosophical prejudice is unavoidable. As a working hypothesis, I consider two types of philosophy: ‘natural philosophy’, seeking for some essence of things, and ‘critical (or analytical) philosophy’, devoted to the analysis of the procedures by which we claim to construct a reality. An extension of critical philosophy, epistemo-analysis (i.e. the psycho-analysis of concepts) is presented and applied to the definition of exolife and to extraterrestrial ‘intelligence’. Some pragmatic conclusions are finally drawn for future search strategies.