In 1985, Carl Sagan was invited to give a series of talks at the University of Glasgow, as part of their long-running Gifford Lectures on natural theology. Over the course of nine lectures, Sagan essentially argues that the best way to “search for God,” if indeed there is one, is through science, replacing wishful thinking with evidence and reason and so on. He draws an interesting parallel between traditional religion and extraterrestrial encounters, both of which make extraordinary claims, lack compelling evidence, and have proponents who let their emotions, their desire to believe, get the better of them.

The lectures were transcribed from audio recordings and then edited by Sagan’s wife and writing partner Ann Druyan, who explains in the introduction how she tried to keep the essence of a live talk while making the text more fit for a book. If Sagan used visual aids in his talk, these are reproduced in the book with his explanatory text by itself on the facing page. The overall effect is a wonderfully readable book that also transports you to the lecture hall, hearing Sagan’s singular speaking style and wit. Almost every lecture is accompanied by a transcription of the Q&A, which further puts one in the room, pondering the Cosmos.