A Light in the Dark

*note: This is a slight update for a review originally published in February of 2001

Sagan's subtitle for this book, "Science as a Candle in the Dark," says much of what he wishes to convey, that is, that science is wondrous, awe-inspiring and liberating. Ignorance (particularly willful ignorance) is just the opposite--a burden that binds one among falsehoods, creating a vulnerability to con men, not only those selling the proverbial snake oil, but also those in the guise government or clergy. Especially in the latter chapters of his book, he describes the social implications he sees for the burden of ignorance--loss of personal and social liberties, hopelessness, poverty, and ill-health.

When I first read this book some years ago, I was unaware that Sagan was terminally ill, yet I got a sense of a man looking back on his life to see triumphs and disappointments. The preface opens with a series of childhood recollections of reality testing. "How can you tell if someone is only imagining?" the boy Sagan asks himself.

The question does become a recurring theme with respect to those who have seen ghosts or been abducted by aliens. Not without compassion, Sagan debunks these step by step. He also tackles such things as the "face" on Mars, spiritualism, the traditional religious visions.

He does not stop there, teaching that healthy skepticism, rather than cynicism, is the best means of reality testing. He refers to this as "The Baloney Detection Kit," which included Occam's Razor and a list on standard logical fallacies. Lastly, he describes both the need and the method of controlled experimentation.

"Like all tools," Sagan writes, "the baloney detection kit can be misused, applied out of context, or even employed as a rote alternative to thinking. But applied judiciously, it can make all the difference in the world..." (p. 216)

In the chapter, "When Scientists Know Sin," he examines ethical problems that arise with science and technology, making it clear that he sees scientists as every bit as human, warts and all, as the nonscientist.

I've found myself rereading bits and pieces of the book in the years since I first read it, drawn to it not so much for its baloney detection advice as to its humanity. Sagan is never dismissive or condescending, even when talking about things like alien abduction that he clearly sees no reality in. He is frank about sometimes hearing the voices of his deceased parents, and admits to missing them very much and wanting assurances that they are all right, and to tell them about their grandchildren. He sees his own vulnerability in these areas, and understands the same in other people.

"But that doesn't mean I'd be willing to accept the pretensions of a 'medium,' who claims to channel the spirits of the dear departed, when I'm aware the practice is rife with fraud." Later in the same section he states, "Better the hard truth than the comforting fantasy."
(pp. 203-204)

The book is dedicated to his grandson, Tonio with these words, "I wish you a world free of demons and full of light." From my reading of this book, this is Sagan's wish for all humans, along with a warning that it is our job to bring it about through a bit of work.