Just about everyone’s had a day when they’ve wished it were possible to send an alternate self to take care of unpleasant or tedious errands while the real self takes it easy. In Kiln People, David Brin’s sci-fi-meets-noir novel, this wish has come true. In Brin’s imagined future, folks are able to make inexpensive, disposable clay copies of themselves. These golems or “dittos” live for a singl...