One reason cultural capital ties literary novelists in knots is its abolition, in Bourdieu’s words, of “the sacred frontier which makes legitimate culture a separate universe.” Writers since at least the heyday of Gore Vidal have bemoaned their audience’s defection to other forms of entertainment. But pop-Bourdieuvianism deprives them of the sense of high-canonical purity with which they’ve traditionally consoled themselves.

To try to reclaim either purity or audience by drawing aesthetic bright lines, as Smith and Franzen do, is to run into another problem: Bourdieu’s ideas aren’t properly aesthetic at all. Note his subtitle: “A Social Critique of the Judgment of Taste.” In chalking up judgment to factors beyond the thing we’re judging, “Distinction” remains agnostic about that thing’s internal particularities. A wink is as good as a nod to a blind horse. To hell with style, then; the novelist now has to confront the larger problem of what the novel is even for — assuming it’s not just another cultural widget.

“The Marriage Plot” proposes its answer in the scene where Madeleine discovers Roland Barthes’s “Lover’s Discourse”: “It wasn’t only that this writing seemed beautiful. . . . What made Madeleine sit up in bed was something closer to the reason she read books in the first place. . . . Here was a sign that she wasn’t alone.” And if this last line sounds familiar, it’s because you’ve probably heard it before.

The idea that “the deepest purpose of reading and writing fiction is to sustain a sense of connectedness, to resist existential loneliness” crops up all over the writing of the Conversazioni group: in Franzen’s nonfiction, and in Wallace’s, and in Smith’s beautiful encomium to Wallace in her book of essays, “Changing My Mind.” It also helps to explain these writers’ broad turn away from various postmodern formalisms and toward the problems of the human heart. Indeed, when we consider the web of influence that connects them to old roommates and friends and lovers and students — a list that includes David Means, Rick Moody, Mary Karr, Donald Antrim and Jonathan Safran Foer — and to newer work by writers like Karen Russell or the Irish novelist Paul Murray, “Here is a sign that you’re not alone” starts to look like the ascendant trope of and about literature today.

Its problem, as a mission statement, is not that it’s symptomatic of our self-help culture; Aristotle saw narrative as therapeutic, too. It’s that it’s not specific enough. Does “the sign that we’re not alone” ultimately refer back to the solitary reader, as Wallace often suggests? (“If a piece of fiction can allow us imaginatively to identify with a character’s pain, we might then also more easily conceive of others identifying with our own.”) Or does it refer to the author, as in Franzen’s “Why Bother?” (“Simply to be recognized for what I was, simply not to be misunderstood: these had revealed themselves, suddenly, as reasons to write.”) Or does truly great literature point to some third thing altogether?

This is where “The Marriage Plot”’s titular enjambment of literature and love — those two beleaguered institutions — is so clarifying. Think about it: I can love you because I want to feel less alone, or I can love you because I want you to feel less alone. But only the latter requires me to imagine a consciousness independent of my own, and equally real.

So far, our new leading novelists have cleared this second hurdle only intermittently. In Smith’s “Autograph Man,” in Franzen’s “Strong Motion,” in the otherwise dazzling “Mister Squishy,” and, alas, in “The Marriage Plot” itself, we encounter characters too neatly or thinly drawn, too recognizably literary, to confront us with the fact that there are other people besides ourselves in the world, whole mysterious inner universes. These works may delight us, but they do not instruct.

I’m cribbing these words — “delight,” “instruct” — from a 2,000-year-old theory about the purpose of art because they seem today more apposite than ever. Even as you read this, engineers in Silicon Valley are hard at work on new ways to delight you — gathering the entire field of aesthetic experience onto a single screen you’ll be able to roll up like a paperback and stick in your back pocket. It’s safe to say that delight won’t be in short supply, and as long as there’s juice in the battery, we won’t have to feel alone. But will we be alone? Literature, to a degree unique among the arts, has the ability both to frame the question and to affect the answer. This isn’t to say that, measured in terms of cultural capital or sheer entertainment, the delights to which most contemporary “literary fiction” aims to treat us aren’t an awful lot. It’s just that, if the art is to endure, they won’t be quite enough.