In Robert Charles Wilson’s new novel The Affinities, as in many of his other novels, the world as we know it is about to be remade. The difference with many of Wilson’s previous works is that, this time, the change seems relatively mild—or at least, at first it does. There are no aliens. There are no disappearing continents or mysterious artifacts from the future or impermeable spheres surrounding the entire planet.

Instead, the big change arrives gradually, brought on by very human advances in social teleodynamics. New technologies, algorithms and testing methods allow a company known as InterAlia (“Finding Yourself Among Others”) to sort people who pay a modest testing fee into twenty-two Affinities. The members of each affinity are supposed to be hyper-compatible: they are more likely to cooperate with each other in all areas of life, from the personal to the professional.

Adam Fisk is one of the people who takes the InterAlia test and finds himself admitted to the Tau Affinity. Before attending his first Tau meeting, Adam is a bit lost in life: he is studying graphic design in Toronto, funded by his grandmother because he’s estranged from almost everyone else in his more conservative, business-oriented family in upstate New York. When Grammy Fisk passes away, the latent conflicts in his family explode—but luckily, the members of his new Tau group are there to fill the gap. So begins Adam’s new life in Tau, during a turbulent period in which the entire world will be changed by the new social structures known as the Affinities…

Oddly, what’s most interesting about The Affinities is also what’s most frustrating: there’s a great deal of vagueness surrounding the whole concept of teleodynamics in general and the differences between the various Affinity groups in particular.

As for the first, Robert Charles Wilson is very careful about emphasizing that the Affinities involve much more than a souped up Myers-Briggs-style personality test. As the person who administers Adam’s Affinity test explains:

A lot of modern science is concerned with understanding patterns of interaction. In heredity, that’s the genome. In how DNA is expressed, we talk about the proteinome. In brain science it’s what they call the connectome—how brain cells hook up and interact, singly or in groups. Meir Klein invented the word socionome, for the map of characteristic human interactions. But each affects the others, from DNA to protein, from protein to brain cells, from brain cells to how you react to the people you meet at work or school. To place you in an Affinity we need to look at where you are on all those different maps.

So getting tested for an Affinity involves the standard psychometric associative tests we all know and love, but also brain-mapping and blood samples and genetic testing. It’s a multi-day process involving advanced technology and testing algorithms that (at least for the moment) are exclusively available to InterAlia.

However, the whole concept of an Affinity just never feels solid in the novel. Adam becomes a Tau, attends his first Tau “tranche” meeting (a tranche being a group of thirty or so people in the same Affinity) and, wonder of wonders, gets along swimmingly with everybody. He experiences something insiders call “tranche telepathy”—the sensation of instantly connecting with someone to the point where you feel you can finish each other’s sentences, even if you’ve never met them before. In one night, despite most people in the tranche being very different from him in terms of almost any demographic we measure today (age, gender, race, …) Adam basically feels like he’s found his very own long lost tribe—but exactly what causes this stays in the realm of hand-waving, about as well-defined as the science behind an FTL drive in a space opera novel.

A second, connected part of the same problem is that Wilson just doesn’t diversify the various Affinities sufficiently. The novel is told from Adam’s perspective, and since Adam is a Tau, that’s the Affinity we learn most about. Aside from one other Affinity (called “Het”—all affinities are named after letters in the Phoenician alphabet) and a brief meeting with a third group that’s deciding whether they want to align themselves with Het or Tau, we learn as good as nothing about the others. Taus are intuitive networkers, financially savvy, and like to smoke pot. Hets rely on rigid hierarchy and following orders passed down from above. Aside from Het and Tau there are three other “large” Affinities and seventeen smaller ones, but after reading the novel I’d be hard-pressed to tell you anything significant about them. And that, for a novel titled The Affinities, is a problem.

As you’d expect from a Robert Charles Wilson novel, there’s plenty of focus on the characters’ personal lives too, or at least on the main character Adam’s. This is an aspect of Wilson’s works I’ve always enjoyed: the way the characters’ lives and romantic entanglements and professional developments interweave with the wider plot. Unfortunately, The Affinities is a bit of a letdown in this respect too. The contrast between Adam and his obnoxiously racist and offensive father is so overemphasized that it borders on caricature, and the way this plays out across the story is somewhat predictable. Even worse, and keeping it vague to avoid spoilers, I found the entire storyline of Adam’s erstwhile girlfriend Jenny simply painful to read.

By far the best part of the novel comes early on, when Adam is growing his network of relationships with the members of his Tau tranche. Initially, it’s just a lot of fun to watch Adam settle into his new “tribe” and see how this group of very interesting and diverse characters interacts, helping and protecting and supporting each other. I just wish we’d gotten more glimpses of the internal dynamics of other Affinities.

And yet. Wilson’s prose is lovely as always, and the concept of the novel is fascinating, if imperfectly developed. In the end, The Affinities is not a bad novel, but from an author who routinely delivers “great,” merely “good” feels like a bit of a letdown. Looking at Wilson’s impressive bibliography thus far, I don’t think many people will rank The Affinities near the top, but that doesn’t mean it’s a book you should skip if you like the author as much as I do. (Or, obviously, if you have any interest in sociology.) A minor Robert Charles Wilson novel, then, but still: a new Robert Charles Wilson novel is always cause for celebration.

This review was originally published at Tor.com on April 20th, 2015. (I forgot to post it here all this time!)