That question was presented on Thanksgiving Day to Nobel laureates and other heavy thinkers by New York author and literary agent John Brockman. Brockman, who presides over an eclectic gathering of scientists and science buffs, started publishing the answers this week on the group's Web site. More than 100 participants have taken the bait so far, and their answers are as varied, and in some cases as strange, as the participants themselves.....This is not a group that accepts limitations gladly. Some fudged on the dates. Some eschewed the notion of an invention as some sort of gadget, opting instead for such things as the development of the scientific method, mathematics or some religions.