The Fermi Paradox: The Cosmic Quarantine Hypothesis

The Cosmic Quarantine Hypothesis resembles, in many ways, the notion of the Prime Directive as found in the Star Trek series of science fiction shows. The hypothesis proposes that advanced species with interstellar capacity may well be common but that they are deliberately shielding their existence from us for one reason or another, e.g. to protect our cultural development. Many variants of the CQH add the additional hypothesis that we will be granted access to the galactic community once we obtain a sufficient level of development.

Many people find the CQH to be an example of paranoid thinking in as much as it indicates a conspiracy of silence by vast powers beyond our reckoning. They note that not only would there have to be a quarantine against visits to our world, but that there would have to be a perfectly enforced quarantine on radio communications and other detectable manifestations of extraterrestrial intelligences, including ones from species near our own level of development. Supporters of the CQH tend to reply that such a "conspiracy of silence" would represent no more effort than setting up a duck blind for a sufficiently advanced species or set of species.