Three Laws of Robotics card-readers in "The Caves of Steel" have a capacity of only a few kilobytes per square centimeter of storage medium. "Aurora", in particular, presents a sequence of historical developments which explains the lack of nanotechnology — a partial retcon, in a sense, of Asimov's timeline. There are three Fourth Laws written by authors other than Asimov. The 1974 Lyuben Dilov novel, "Icarus's Way" (a.k.a., "The Trip of Icarus") introduced a Fourth Law of robotics: Dilov gives reasons for the fourth safeguard in this way: "The last Law has put an end to the expensive aberrations of designers to give psychorobots
Sci-Fi Valley Con Sci-Fi Valley Con Sci-Fi Valley Con is an annual three-day speculative fiction (science fiction and fantasy, or SF) convention had in Altoona, Pennsylvania at the Blair County Convention Center; it is promoted by Assett Conventions, LLC (solely owned and operated by Casey B. Bassett) and is the first such convention in the area. The convention has featured a variety to different forms of entertainment over the years in order to drawl in the visitors, such as; Magic: The Gathering, HeroClix, & Warhammer 40,000 tournaments, video game tournaments, trivia tournaments, costume contests, guest speaking panels, film festival, dealers, artists, charity auctions,