Does all intelligent life face a Great Filter?
“Where is everybody!?”
It was around 1950. UFO mania had recently ramped up across the world, with dozens of reported sightings of strange flying machines fueling rampant speculation regarding their origins.
The eminent physicist Enrico Fermi was visiting his colleagues at Los Alamos National Laboratory in New Mexico that summer, and the mealtime conversation turned to the subject of UFOs. Very quickly, the assembled physicists realized that if UFOs were alien machines, that meant it was possible to travel faster than the speed of light. Otherwise, those alien craft would have never made it here.
