And the Term is . . . Congeries
What distinguishes a congeries novel from a story collection that is set in a single imaginative universe (as John Varley and others have done) or from a sequence of stories that has continuing characters (like Spider Robinson’s Callahan series) is the combination of individual integrity of the parts -- they are not merely chapters -- and the unitary shape of the whole. The end result should be like a wall in the Barnes Museum, where each canvas is a discrete work of art, but their arrangement creates a unique and greater effect.
Hard and fast borders are impossible to draw. The sections of Isaac Asimov’s “I, Robot” all deal not only with emerging robot technology but with a single individual, Susan Calvin. But the sections deal with Calvin at non-continuous periods of her life; we don’t get a full portrait. The stories are told from slightly different points of view, and the reader is definitely left with a sense of a series of glimpses that leave questions unanswered. That sense of lacunae, a deliberate artistic tactic, is a sign of the congeries. “I, Robot” may be a borderline case, but I would say that it qualifies.
That, I think, is the truly distinguishing trait of the congeries novel, a first-rate one, anyway: the sense that its crucial constituents include the gaps between the existing sections, the tension in the field of force these disparate elements exert. Gene Wolfe’s “The Fifth Head of Cerberus” (a brilliant novel) does this, as does “Pavane” and “The Seedling Stars.” (“China Mountain Zhang” is a fine novel, but it does not greatly exploit these particular traits.)
So what characterizes the congeries novel is the disparate nature of its makeup, the tension between these levels of organization, and the sense that the intervals between sections possess a force and weight of their own. (Notice how all of these characterize, say, “The Waste Land.”) Which is to say, the congeries novel is a thoroughly Modernist phenomenon.