Lonely Planets: The Natural Philosophy of Alien Life

Where do planetary science and philosophy intersect? In one fascinating field: the search for extraterrestrial life. Today on Focus, David Grinspoon speculates about the possibility of life on other planets and in other solar systems, how intelligent life may evolve both on our own planet and in the rest of the universe, and what the philosophical implications of these future discoveries may be.

Guest: David Grinspoon (planetary scientist at the Southwest Research Institute; author of Lonely Planets: The Natural Philosophy of Alien Life)