Published 39 years ago in 1979, Isaac Asimov discussed the possibilities of finding intelligent life in his book Extraterrestrial Civilizations. This has been on my reading list for quite a long time, but I just now got the notion to mark it off. Having read literally all of Asimov’s fiction, I thought it was time to read more of his non-fiction. Unwittingly, I finished this just a week or two before his birthday, which by the way was 99 years ago today!

I was thinking Extraterrestrial Civilizations would be a discussion on what civilizations might be like when if/when we discover them, or they discover us. It turned out to be more of a thought experiment, methodically laying out probabilities based on list of assumptions. Most of these assumptions were made with what scientific knowledge there was available at the time. Asimov was very careful to speckle the book with asterisks noting that if certain assumptions would change in the future, the predictions would be changed or invalidated. Read more…