The universe is a pretty big place. If it's just us, seems like an awful waste of space.

The quote compresses an argument from scale into a memorable aphorism: if the universe contains billions of galaxies and vastly more stars and planets, it feels improbable that life happened only once. “Waste of space” is rhetorical rather than literal—space is not built for a purpose—but it highlights the tension between human self-importance and cosmic perspective. Sagan’s deeper point is epistemic humility: our intuitions are not proof, yet the immensity of the cosmos makes the search for life elsewhere reasonable and scientifically motivating. It also frames SETI as a natural extension of curiosity rather than fantasy.