The Argument: Should We Say "Hi" to Aliens?

We're taking this week off from publishing new episodes, so today we're bringing you an episode from "The Argument" about one of my favorite topics: aliens. We'll be back with new episodes of "The Ezra Klein Show" on Tuesday. With the U.S. government puzzling over U.F.O.s, and potentially habitable exoplanets in our telescopes, earthlings are closer than ever to finding other intelligent life in the universe. So the existential question is: Should we try to communicate with whatever we think might be out there? That’s the argument this week between Douglas Vakoch and Michio Kaku. Vakoch, the president of the research and educational nonprofit METI (Messaging Extraterrestrial Intelligence) International, has dedicated his life’s work to intentionally broadcasting messages beyond our solar system. Kaku, a professor of theoretical physics at the City College of New York and a co-founder of string field theory, thinks reaching out to unknown aliens is a catastrophically bad idea and “would be the biggest m