The Fermi paradox is the discrepancy between the lack of conclusive evidence of advanced extraterrestrial life and the apparently high likelihood of its existence. Those affirming the paradox generally conclude that if the … See more

Fermi was not the first to ask the question. An earlier implicit mention was by Konstantin Tsiolkovsky in an unpublished manuscript from 1933. He noted "people deny the presence of … See more

Rarity of intelligent life
Extraterrestrial life is rare or non-existent
Those who think that intelligent extraterrestrial life is (nearly) impossible argue that the conditions needed for the evolution of life—or at least the evolution of biological complexity See more

• Boyle, Rebecca; et al. (Quanta Magazine) (March 10, 2019). "Moving Stars Might Speed the Spread of Alien Life". The Atlantic See more

The following are some of the facts and hypotheses that together serve to highlight the apparent contradiction:
• There … See more

There are two parts of the Fermi paradox that rely on empirical evidence—that there are many potentially habitable planets, and that humans see … See more

• Aestivation hypothesis – Hypothesized solution to the Fermi paradox
• Anthropic principle – Hypothesis about sapient life and the universe
• Astrobiology – Science concerned with life in the universe See more