Engines of Creation
K. Eric Drexler
 The book features nanotechnology, which Richard Feynman had discussed in his 1959 speech There's Plenty of Room at the Bottom. Drexler imagines a world where the entire Library of Congress can fit on a chip the size of a sugar cube and where universal assemblers, tiny machines that can build objects atom by atom, will be used for everything from medicinal robots that help clear capillaries to environmental scrubbers that clear pollutants from the air. In the book, Drexler first proposes the gray goo scenario—his prediction of what might happen if molecular nanotechnology were used to build uncontrollable self-replicating machines. Topics also include hypertext as developed by Project Xanadu and life extension. Drexler takes a Malthusian view of exponential growth within limits to growth. He also promotes space advocacy arguing that, because the universe is essentially infinite, life can escape the limits to growth defined by Earth. Drexler supports a form of the Fermi paradox, arguing that as there is no evidence of alien civilizations, "Thus for now, and perhaps forever, we can make plans for our future without concern for limits imposed by other civilizations."