The problem with the Fermi paradox is that it requires you to assume the existence of spacefaring civilizations, with all the expected technology. The possibili

The problem with the Fermi paradox is that it requires you to assume the existence of spacefaring civilizations, with all the expected technology. The possibilities are just to many, and we only know relatively well our own solar system, we don't know how normal it is (recent observations suggests it could be at least kind of odd) or how normal Earth is. As it is quoted, Earth for us is all there is and it would seem completely normal to us even if for any well educated alien it could look obviously artificial. The Black planet hypothesis: There are planets intentionally cut off the bigger society. Spacefaring civilizations are largely immortal, and would be kept in an evolutionary stasis, so there are planets that are intentionally kept isolated and prisoners are kept on them in a pre galactic stage as a way to keep evolving. Impending doom hypothesis: An immense catastrophe is expected to happen in the general area, and all the surrounding space has been evacuated. Presumed recluse hypothesis: Our solar system is recognized as obviously artificial, yet attempts to communicate are met with no response. We are perceived as unwilling to communicate and intentionally left alone. Planets are primitive hypothesis: More advanced civilizations have no interest in settling planets, planets are seen as primitive as living in a rainforest is to us, while advanced civilizations normally live in artificial habitats. Unpleasant star hypothesis: The solar wind, neutrino flow or other forms of radiation may be disruptive to highly advanced technology, so the sources are avoided unless necessary.