Question
What is the definition of intelligent life? Is it the abilty to analyze situations and react in the correct way, or is the complexity the primary issue?
This is a diffficult question, and I have never found a satisfactory answer. This question is sometimes addressed in books and articles on SETI (for example, in "Extraterrestrials: Science and Alien Intelligence", edited by Edward Regis, Cambridge University Press, 1985), but from the SETI perspective intelligence must include the ablity to transmit and receive signals over interstellar distances (that is, technological intelligence). More generally, Carl Sagan wrote (in "Cosmic Connection," recently reprinted by Cambridge University Press) that intelligence involves the tendency toward control of the environment -- including a non-hereditary adaptive quality developed during the lifetime of a single individual (that is, intelligent creatures can learn). Other more recent definitions have been suggested by those working in the field of artificial intelligence. Good luck with this pursuit!
David Morrison
NAI Senior Scientist
May 6, 2004