There are those who still contend Carl Sagan was not a "deep thinker". Perhaps they're correct, but the scope of his interests and his ability to impart them are unimpeachable. And peerless. The expressive and often humorous voice of science Sagan projected to an admiring public surely garnered a significant percentage of those students entering the discipline. If he left no other legacy, from plates on space probes or searching for alien life, that one is among the most admirable. Yet, that powerful intellect provoked many by issuing challenges to be answered. This collection of twenty-year-old lectures is one such thrown gauntlet. Presented to an audience which responded enthusiastically to his views, Sagan offered a redefinition of how they might view their god. As always, he did it with delightful wit and from a basis of extensive study and experience.
The Gifford Lectures centre on what's called "Natural theology". The term applies to using scientific methods to support theology. One can only hope that by 1985, the members of the audience knew of Sagan's thinking prior to his emergence on stage. From the opening lecture, "Reconnaissance of Heaven", Sagan strips away old mythologies relating how the cosmos worked. In nine lectures and a following question and answer session, he reveals the scope and workings of our universe that science has revealed. The key factor, of course, is "evidence". What we have learned about the world around us is derived from centuries of hard work by dedicated workers. The effort, performed in small, but incremental steps, has revealed a universe over 14 billion years old. It is populated by more galaxies than there are stars in our Milky Way, with each of those cosmic gatherings themselves populated by their own billions of stars. Yet, with all those fantastic numbers, Sagan reminds us, there is a uniformity among that host of fiery orbs. Sodium here is the same as that at the edge of our perception. Organic molecules, without which life could exist nowhere, are present everywhere. What are the odds that we humans are the sole intelligent life?
Extraterrestrial life and the implications arising from that possibility, form a sub-theme of the series. From the suggestion that so many stars exist, it naturally follows that many of them have planets, some of which ought to be capable of hosting life, perhaps even intelligent life. It's only logical that such life would also seek who might be residing as cosmic neighbours. Sagan explains the famous Drake Equation, which postulated the odds of such life existing. It hasn't been found, he admits, but that's no reason not to search for it. In his lectures, he supposes that in other places, intelligent life might last millions of years. That life might - ought - to be well in advance of ours. Furthermore, he contends, what does such life imply for our concept of a god who fashioned us and our beliefs? Is it rational, he asks, to think a universe as vast as ours should be initiated, let alone controlled, by a human-devised supernatural being?
Before an audience interested in nature and theology, Sagan posits a new concept of a god. Not one with supernatural powers and dabbling in affairs of a single species on a remote planet, but something different. This deity should represent the expanse and complexity of the universe we are only beginning to understand. He explains how older versions of deities hampered scientific investigation - they're still doing so. A new, less defined and more open concept of the spiritual aspect of the universe is in order. Entirely new religious experiences can derive from redefining our relationship to the universe, one more realistic and, in Sagan's view, much grander and more fulfilling. This concept, of course, underlies the book's title. By adapting William James' highly insightful, if less informed, work of human religiosity, Ann Druyan, Sagan's wife and collaborator, gave a "tip of the hat" to that earlier collection. "The Varieties of Religious Experience", a previous Gifford Lectures series, also sought a broadened sense of spiritual values. James' work needed little "updating", but Druyan offers some examples of what has been learned in the two decades since her husband's lectures to fill in meaningful details. Sagan would have applauded, since each new bit of information buttresses his case. [stephen a. haines - Ottawa, Canada]