Deep Time: How Humanity Communicates Across Millennia [Anglais] [Broché]

This book is really two different books connected by a quick segue. The first half of the book sprints through a summary of the different ways that humans have intentionally left evidence of their lives long after their death. It continues to chronicle recent and ongoing efforts to leave evidence of our civilization to future humans and in outer space. I found the discussions of the petty infighting at NASA and the chaotic process of government-sponsored monument design particularly interesting. Benford is quick to note that for the money we spend on a radioactive waste marker that might save 100 lives over 10,000 years, we could save many thousands of lives right now. Comments like these help the reader keep a grounded perspective of the silliness of leaving long-lasting monuments, as well as highlighting the drive that makes us ignore our present concerns in favor of leaving messages for future generations.

The second half of the book is entirely about how future generations will interpret the environmental state of the planet as a monument to our current society and how we can take action to change the state of the planet. This section strays more heavily into the realm of speculative fiction than the first half of the book. Benford argues for "responsible stewardship" of the planet as the only option for sustaining our current level of population and energy. He calls for active efforts to influence the patterns of energy exchange over the planet's surface. While he is almost certainly right, his argument is a bit aggressive. He warns that we must start with extremely limited experiments, but does not stress the fact we do not yet have the mathematical modeling techniques to accurately assess and predict the worldwide effects of our experimentation. My only real criticism of the book is that it implies that we are capable of responsibly taking large scale action today, even though it may still be decades before ecosystems modelers will be able to provide the kinds of analysis that will allow humanity to become responsible stewards of the planet.

This book really gets you thinking in a new way: going beyond your own petty life and petty concerns to think about the far past and the far future. So you think computer disks are so cool? Egyptian pyramids have a better record of surviving down the ages - already some of our data media are disintegrating and we don't have any working equpment to read them! When you call something the "way of the future," Benford points out, you need to think about exactly how far in the future you are looking.

Time capsules? We go to so much trouble to send trivial junk into the future...sometimes for only a few decades. A future archaeologist would probably learn more from mining our landfills, as we do from digging in ancient garbage heaps.

Benford also distinguishes between serious, scientific efforts to send a message to aliens (eg the plaques/records on the Pioneer space probes) and the "Kilroy was here" impulse ("Send your name on a CD-ROM to the stars!") being marketed so heavily. The latter, he notes, amounts to graffiti, worthless in the end except to someone's ego.

Finally, there are sections on saving the environment and biodiversity, to make sure we HAVE a future. Benford strikes a balance between the in situ/ex situ (conservation/zoos) approaches to saving species and the Puritan/technology prophet approaches to solving the greenhouse effect, a balance that is desperately needed when most so-called experts seem to be passionate ideologues one way or the other.

This book draws broadly on numerous disciplines and from a lot of research but leaves you really thinking in the end, and perhaps rethinking some of your assumptions about the future.

I very much enjoyed reflecting on the ideas presented in Benford's discussion. The content and organization of the book are not specifically addressed in previous reviews on this site, so for the reader wondering what the book is about, a road map might be useful.
Deep Time has four sections:
(1) Ten Thousand Years of Solitude describes a project in which the author was involved, which addressed how (or if) society can design safe repositories for nuclear waste with effective means of communicating across millenia to people who will not share our culture, technology, or language, "don't go near this place." Past epic attempts to communicate over the millenia and present attempts to preserve computer data for even a few years do not build confidence that this critical message will speak properly to its unimaginably distant audience.
(2) Vaults in Vacuum is a rather darkly amusing discussion of the etched plates NASA sent out on some space missions intended to communicate with whoever finds them about Earth, Sol, and humans. The unintended humor of the political process surrounding their design communicates more to us about human nature than the disks themselves could ever communicate to aliens! The fate of the diamond disk that was supposed to ride with Cassini-Huygens to Saturn is nothing short of hysterical.
(3) The Library of Life is a depressing description of the potentially Chicxulub-scale loss of biodiversity caused by humans in the last few centuries. It argues almost poignantly, perhaps quixotically, for building cryogenically-preserved DNA libraries to store the basic information on biodiversity, so our far descendants, if we manage to leave any, might be able to resuscitate what we are destroying -- "Jurassic Park" on ice.
(4) Stewards of the Earth: The World as Message is a vaguely postmodern discussion of the earth we're leaving behind us for our descendants as a text and what that text reveals about us. The message is not flattering or hopeful. Should human society with its next-quarter or, at most, decades time frame begin to design and effect centuries-long agendas to assist the planet to support us at a high level of technological civilization, our primate cleverness may yet evolve into wisdom and conscious design of what the earth says about us to our long-distant descendants.