David Lavery argues persuasively that those intrigued by the challenge of perfecting a world ruled solely by human artifice are increasingly committed to abandoning the Earth. Writers ranging from physicists to rock stars salt their works with references—which Lavery calls "evolutionary Freudian slips"—revealing genuine "extraterrestrial urges." Because metaphors of space are now ubiquitous, Lavery rejects C. P. Snow’s dichotomy separating science from the humanities; the true split now is between Earthkind and Spacekind.Firmly committing himself to the Earth—humanity’s last link to nature—Lavery notes that "for those who now insist upon the necessity and calculate the means of escape from this planet, the Earth itself is often left out of the equation." Those who are "late for the sky," those who with "infinite presumption" have "persuaded themselves (and seek to convince us all) that human longing for the stars is not a betrayal of human destiny but in reality its apotheosis; their conviction that the species has been given a cosmic mandate to inseminate the universe with the human…all testify to minds seldom any longer on the Earth."