<-- Golden Goo | Transhumanist Terminology Index | Grey Goo -->
A
hypothetical mechanism or
principle by which the great number of potentially
life-bearing planets get filtered out before they have
produced
intelligent life forms that expand into the cosmos. Related to
the Fermi Paradox.
Often thought of as relating to those levels of technology where destruction of the species, or at least a return to very low technology states, is a very real possibility, and that most civilizations are unable to make it through this period without using the technology for these destructive uses.
It can also be applied to various obstacles that may be present in the development of life on a planet, and it's evolution. The anthropic principle guarantees that a failure case can't ponder these questions, so only a form of life that's successfully made it can, so we cannot make any deduction about how likely/unlikely life is based on our existence.
The existence of this filter, and when it occurs, are of interest to what it can mean. If one does exist, it does help explain away the Fermi paradox - it's why we don't see life, or at least traces of life, around the universe. And if it does exist, when it occurs is also important. If we're past it, or most of it, then our future looks bright when we think about us spreading off the planet and into space. But if most of it is ahead, then it means we have some serious danger and problems looming ahead that we have to get around to avoid self-destructing.
Whether or not this exists, and functions according to the first case, there is still the very real concern on this planet that we may not be able to resist using the technology for destruction long enough to either establish defenses to make it's dangers minimal/non-existent, or long enough to get at least some portion of society out of the range of the rest, should they use that technology.