Is this some Posadist thing?
The Posadists were an apocalyptic cult with absurd ideas about nuclear war and comradeship with dolphins, but their party line on aliens was pretty sound.
In this one respect, the Posadists’ view overlapped with that of Carl Sagan, the American cosmologist who helped provide a scientific rationale for the belief that our galaxy is full of advanced civilizations. (He guessed somewhere between 50,000 and 1 million.) Sagan’s estimate was based on his assumptions about the Drake equation, which multiplies the number of planets that can sustain life (R* · ƒp · ne · ƒl) by the likelihood that intelligent life is able to signal its existence across space (ƒi · ƒc) and the length of time these civilizations can send such detectable signals (L) to arrive at the number of civilizations that are capable of interplanetary messaging (N). We have one data point for N: humanity.