The Voyager 2 space mission was to fly to the outer edges of our solar system and send back data. The Voyager 2 included recordings of music, human sounds, an EEG recording, and other representations of human civilization. If an extraterrestrial were to find it, we wanted it to show them who we were. Some people have thought the idea of intelligent extraterrestrials to be crazy, and others have thought of it as a certainty. Pinker argues that it is unlikely that human-like intelligence has developed elsewhere and that people who argue that it most certainly has evolved elsewhere do not understand how natural selection works. There is an assumption that intelligence is a goal of natural selection, but natural selection does not have goals. The only “goal” that could be ascribed to natural selection is passing on genes. The genes want to make it to the next generation. They do that by being beneficial to most of the population.

Arguably, intelligence would be beneficial to a lot of organisms, but just like any other complex, evolved organ, the human brain and the intelligence it allows are costly. The brain makes up 2% of the weight of the human body but uses 20% of its energy.