In the summer of 1977, humanity sent two spacecraft beyond the solar system carrying not only music, images, and greetings, but something far more intimate: the compressed electrical activity of a young woman's brain, recorded two days after she agreed to marry the astronomer who had asked her to help speak for Earth. The Voyager Golden Record, now more than 25 billion kilometres from home, is less a scientific instrument than a philosophical act — a civilization's attempt to say, across unimaginable distance and time, that we were here, that we felt things, and that some of what we felt was l