Rare Earth Hypothesis

Basic Information

The Rare Earth Hypothesis is the theory that planets, planetary systems, and galactic regions that facilitate the development of complex life as Earth does are rare. This does not rule out microbes and the like, but more complex life is unlikely to develop elsewhere in the universe, according to this theory.

Sources

Bibliography

1. Wikipedia article: Rare Earth Hypothesis

2. TV Tropes entry: Absent Aliens

Game and Story Use

• If Earth-like planets are rare and complex life can only originate from Earth-like planets, then that gives humanity a special place in the universe; it is up to us to spread life throughout the cosmos, that it may not die out with us. If we don't do it, there's a good chance no one will.
  • The seeded life may well come to regard us as Precursors if and when it reaches sapience. Three questions arise from such a situation: are we benevolent precursors, neglectful precursors, or abusive precursors, and are we alive or dead by time they reach beyond their homeworlds?