<human>:  When did the first wheelchair appear in science fiction?
<bot>: The first wheelchair in science fiction was in the book Starship Troopers, by Robert A. Heinlein. In this book, the main character is a soldier who is paralyzed from the waist down. His wheelchair is a space-age design, with a large, flat seat and a hand crank. The main character uses his wheelchair to move around and to carry things.