Dated and dull, Andre Norton's The X Factor is one of those books sitting, lonely and musty and forgotten, on the shelves of used bookstores (or perhaps your own collection), so small and easy to skip over that one can forget that these kinds of pulpy adventure novels were the backbone of SF publishing for many many years. As Norton's career spanned a boggling seven decades, her enormous body of work in SF merits note, even though she's never been one of the genre's greats. But someone whose bibliography is in the neighborhood of 100 books should not be ignored, even when some of them are as drab as this one.
The novel's hero is Diskan Fentress, mutant son of a high-ranking military official who, feeling out of place in a life that requires a certain bearing and poise (he's pitifully overgrown and clumsy), steals a spaceship and runs off to an uncharted world called Mimir to begin a new life. Norton makes the theft of the spaceship ludicrously easy (it amounts to a variation on stealing dad's keys). But clearly Diskan is not the brightest bulb on the tree, either. Crash landing in a frozen, alien wasteland, with barely enough provisions to survive, Diskan soon encounters strange indigenes called the brothers-in-fur. Their ancestors, we learn, inhabited a once-magnificent city named Xcothal, the ruins of which poor Diskan soon finds himself led to. There he meets another human, a girl named Julha Than, and a wounded alien called a Zacathan. He learns that the ruins of Xcothal contain a treasure being sought by a band of outlaws called the Jacks.
The story has little to its credit in the logic or plausibility department, and not much entertainment value either. One could put this down to the book's age — a lot of SF from this time period doesn't read very well any more. But then, the work of SF's grand masters — Asimov, Heinlein — from this period, despite some obviously dated content, holds up nicely because those authors had the skill to imbue their tales with universal themes and concerns that transcend the limitations that SF storytelling faced back then. Norton just lacked that skill.
Diskan is something of a sympathetic hero at first, as he's such a sad loner with problems he cannot help. But after a while he just gets boring. There's nothing about him to relate to. Norton ignores the opportunity to introduce some real emotional trauma into his running away, and the reader doesn't have a stake in his safety or survival. For fully the first half of this short novel, Diskan just wanders Mimir, looking for signs of life. Norton's exposition is interminable. After Diskan meets Julha, things pick up (finally! dialogue!), but the plot proves to be feeble adventure stuff indeed. Today, with the greater sophistication SF has evolved as a literary form, a writer might choose to turn a tale like this into both an adventure story of survival, and an engrossing character study about a brave young man overcoming his handicaps by facing adversity. The possibilities are there. But all we have here is pulp fiction of little consequence and not much fun.