This is also related https://en.wikipedia.org/wiki/Fermi_paradox#Hypothetical_explanations_for_the_paradox https://en.wikipedia.org/wiki/Fermi_paradox#Hypotheti

This is also related https://en.wikipedia.org/wiki/Fermi_paradox#Hypothetical_explanations_for_the_paradox https://en.wikipedia.org/wiki/Fermi_paradox#Hypothetical_exp... and this seems like a good summary: > Some examples of possible resolutions [of the paradox] are that intelligent life is rarer than is thought, that assumptions about the general development or behavior of intelligent species are flawed, or, more radically, that current scientific understanding of the nature of the universe itself is quite incomplete.