Great Filter

Proper noun

the Great Filter

1. A barrier which prevents intelligent life from developing to a level where it can be detected across interstellar distances.
   • Well, maybe that means that there is — the term, I think it’s from the economist Robin Hanson — that there’s a great filter. That basically, it’s so hard to become a multiplanetary species that even though life is everywhere, every species gets stuck somewhere around where we are: Achieving some...2026 February 26, Ross Douthat, “The New Space Race”, in The New York Times, →ISSN
2. The hypothesis that such a barrier exists.
   • While there are plenty of potential explanations and counterarguments for the Fermi paradox, one that has grabbed a lot of attention is known as the Great Filter - the idea that there is some sort of filter that prevents a civilization from becoming advanced enough to traverse the galaxy.2024 March 18, “Exploring the SCP Foundation: SCP-3426 - Reckoner” (0:50 from the start), in The Exploring Series, archived from the original on 30 Mar 2024