From the prologue:
"Imagine an alien who visits Earth once every thousand years ... when he arrives on the third millennium [he] is not surprised to find murder, envy, strife, wars and rumors of wars, vanity and vexation of spirit. ... [he] heads downtown and enters the first one he sees. There he finds a mixed crowd. ... "Why the hopelessness, the sense that life is meaningless?" the alien asks the sullen ones. ... Somehow a group of influential human intellectuals have concluded that science has proven that the universe is essentially meaningless. ... "It isn't about 'proof' anymore", [an iron-haired religion professor] explains. ... [The extraterrestrial] records all of this and returns to his ship and his home on the other side of the galaxy. ... The extraterrestrial are, of course, fiction. The poison, however, is real. This book is written as an antidote."