Science Fiction is speculative literature that generally explores the consequences of ideas which are roughly consistent with nature and scientific method, but are not facts of the author’s contemporary world. The stories often represent philosophical thought experiments presented in entertaining ways. Protagonists typically "think" rather than "shoot" their way out of problems, but the definition is flexible because there are no limits on an author's imagination. The reader-selected stories presented here were written prior to 1962 and became US public domain texts when their copyrights expired. (Summary by Gregg Margarite)