faith, to which he converted after marrying a Catholic. Chris Walley and his "Lamb Among the Stars" trilogy. Walter M. Miller Jr., the author of A Canticle for Leibowitz Tim LaHaye and Jerry B. Jenkins with their Left Behind series. Connie Willis, who explores free will and predestination especially in her time travel novels. Zenna Henderson and her stories about "The People." Criticism Mort argues that one of the difficulties facing Christian science fiction authors who endorse Creationism—especially those writing "hard" science fiction—is reconciling the limits placed on the author in exploring science within a Creationist framework. This is made even more problematic when one considers that the notion of "the future as divinely ordered" limits the author's ability to speculate on what that future may be. For example, the first of these difficulties has been identified by Pierce as a problem with some of R. A. Lafferty's work, who "is uncomfortable with the idea of even biological evolution"; while Tom Doyle notes the predictability of the Christian apocalyptic novel, due, he argues, to the genre following "a particular interpretation of biblical prophecy". These difficulties raise concerns regarding genre boundaries: while Christian science fiction has been identified as a specific market into which stories can be sold, Doyle has questioned whether or not books that are, at times, classified in this subgenre truly fit. In examining Christian apocalyptic fiction, Doyle notes that it is often classified as Christian science fiction, but argues that this classification is inappropriate. While both may employ scientific themes, Christian apocalyptic fiction is not, as he describes it, "scientifically minded", arguing that the authors tend to respond to scientific problems "with biblical authority, prophetic interpretation, and fundamentalist ideas of human identity instead of rational argument, scientific method, and humanistic thought". Doyle sees Brian Caldwell's We All Fall Down as an exception to his argument, suggesting that (despite being a work of Christian apocalyptic fiction) it is the sort of work that he would like to see classified as science fiction. It should however be noted that not all Christian science fiction authors have the same theology. See also List of Catholic Science Fiction and Fantasy authors List of Protestant Science Fiction and Fantasy authors List of religious ideas in science fiction Theological fiction Footnotes References External links Christian Fandom Home Page—Nondenominational (albeit fundamentalist in tendency) fellowship of fans interested in fair, accurate representation of orthodox Christian