The publication of James Geary"s The Body Electric offers evidence that is becoming ever more familiar--and ever more comfortable--with the idea that we live cybernetic lives. We are born in intensive care, and we will die there. We mend our broken hearts with artificial valves; we swallow complex chemical machinery to brush away the difficulties of our lives. To some degree, then, we read Geary"s book purely for comfort: for the thought that, as our own senses begin to fail, cybernetic senses are already being developed that can aid or replace them. As far as that goes, Geary"s take on medical technology is entertaining, enthusiastic and free of bombast. But his shop of wonders is much more than a window display. It"s informed throughout by philosophical concerns that would (and, if Geary"s of a mind, probably should) make books in themselves. There is, for example, his overarching awareness that we are very small, in a very big universe. As such, we can only perceive a tiny fraction of what"s out there. When we look at the real world, it"s more accurate to say that we"re looking at a scale model, filtered by our brains from out of the spew of sensory data with which the world bombards us. This being the case, what are the ethical consequences if we build machines that further filter--or filter in a different way--our experience of the world? The Body Electric describes wonders enough to satisfy the most jaded technocrat, but big questions are never far below the surface.--Simon Ings