The following is adapted from “A Head That Throbbed Heartlike: The Philosophical Mind of David Foster Wallace,” an introduction to Wallace’s undergraduate honor thesis in philosophy, which has just been published by Columbia University Press as Fate, Time, and Language: An Essay on Free Will.

I. “A special sort of buzz”

When the future novelist David Foster Wallace was about 14 years old, he asked his father, the University of Illinois philosophy professor James D. Wallace, to explain to him what philosophy is, so that when people would ask him exactly what it was that his father did, he could give them an answer. James had the two of them read Plato’s Phaedo dialogue together, an experience that turned out to be pivotal in his understanding of his son. “I had never had an undergraduate student who caught on so quickly or who responded with such maturity and sophistication,” James recalls. “This was this first time I realized what a phenomenal mind David had.”

The experience seems to have made an impression on David as well. Not long after he arrived at Amherst College in the early 1980s, he developed a reputation among his professors as a rare philosophical talent, an exceptional student who combined raw analytical horsepower with an indefatigable work ethic. He was thought, by himself and by others, to be headed toward a career as a professor of philosophy. Even after he began writing fiction, a pursuit he undertook midway through college, philosophy remained the source of his academic identity. “I knew him as a philosopher with a fiction hobby,” Jay Garfield, a professor now at Smith College who worked with Wallace at the time, remembers. “I didn’t realize he was one of the great fiction writers of his generation with a philosophy hobby.”

For most of college, Wallace’s main philosophical interests were in the more technical branches of the subject, such as mathematical logic and the philosophy of language. One semester, he took a seminar on the philosophy of Ludwig Wittgenstein, whose early work grapples with the writings of Gottlob Frege and Bertrand Russell, two of the founders of modern logic. As Wallace recollected in 1992 in a letter to the novelist Lance Olsen, he was “deeply taken” in the seminar with Wittgenstein’s first book, Tractatus Logico-Philosophicus (1921). Along with its controversial arguments about the nature and limits of language, the Tractatus introduced some indisputable formal innovations, including a method of analyzing the propositions of modern logic by way of “truth tables.” To some, the book might have seemed forbiddingly spare and exacting; Wallace remembered being moved by its “cold formal beauty.” When the seminar moved on to Wittgenstein’s so-called late philosophy, in which he repudiates the ideas and austere methodology of the Tractatus in favor of new assumptions and a looser, less mathematical style, Wallace was not immediately impressed. He wrote to Olsen that at first he found Philosophical Investigations, the crowning statement of the late philosophy, to be “silly.”

Wallace would later identify his attraction to technical philosophy in aesthetic terms: It was, he suggested, a craving for a certain kind of beauty, for the variety of imaginative experience characteristic of formal systems like mathematics and chess. In an interview with the literary critic Larry McCaffery published in 1993, Wallace explained that as a philosophy student he had been “chasing a special sort of buzz,” a flash of feeling whose nature he didn’t comprehend at first. “One teacher called these moments ‘mathematical experiences,’ ” he recalled. “What I didn’t know then was that a mathematical experience was aesthetic in nature, an epiphany in Joyce’s original sense. These moments appeared in proof-completions, or maybe algorithms. Or like a gorgeously simple solution you suddenly see after filling half a notebook with gnarly attempted solutions. It was really an experience of what I think Yeats called ‘the click of a well-made box.’ The word I always think of it as is ‘click.’ ”

For his honors thesis in philosophy, Wallace continued to chase the click, writing a highly specialized, 76-page work on the metaphysical doctrine of fatalism (which holds, quite radically, that human actions and decisions have no influence on the future). Brace yourself for a sample sentence: “Let Φ (a physical possibility structure) be a set of distinct but intersecting paths j i – j n , each of which is a set of functions, L’s, on ordered pairs ( ), such that for any L n , L m in some j i , L n R L m , where R is a primitive accessibility relation corresponding to physical possibility understood in terms of diachronic physical compatibility.” There are reasons that he is better known for an essay about a cruise ship.

II. An “artistic and religious crisis”

One of the many impressive aspects of Wallace’s work on the thesis was that he was able to sustain his philosophical focus long after having begun a countervailing transformation: from budding philosopher to burgeoning novelist. The transition was set in motion toward the end of his sophomore year, when a bout of severe depression overcame him. He left school early and took off the following term. Wallace would suffer from depression for much of his life, and he tended to avoid public discussion of it. On a rare occasion in which he did allude publicly to his hiatus from Amherst, in his interview with McCaffery about a decade later, he described the episode as a crisis of identity precipitated by mounting ambivalence about his future as a philosopher. “I was just awfully good at technical philosophy,” he said, “and it was the first thing I’d ever been really good at, and so everybody, including me, anticipated I’d make it a career. But it sort of emptied out for me somewhere around age twenty.”

A debilitating panic followed. “Not a fun time,” he went on. “I think I had a kind of midlife crisis at twenty, which probably doesn’t augur well for my longevity.” He moved back home to Illinois, “planning to play solitaire and stare out the window,” as he put it—”whatever you do in a crisis.” Though he now doubted that he should devote his life to philosophy, he was still drawn to the topic and found ways to engage with it, even dropping in on a few of his father’s lectures at the university, where he monopolized the discussion. “He came to some of my classes in aesthetics, and tended to press me very hard,” James Wallace told me. “The classes usually turned into a dialogue between David and me. The students looked on with ‘Who is this guy?’ looks on their faces.”

During this time, Wallace started writing fiction. Though it represented a clean break from philosophy, fiction, as an art form, offered something comparable to the feeling of aesthetic recognition that he had sought in mathematical logic—the so-called click. “At some point in my reading and writing that fall I discovered the click existed in literature, too,” he told McCaffery. “It was real lucky that just when I stopped being able to get the click from math logic I started to be able to get it from fiction.” When he returned to Amherst, he nonetheless resumed his philosophical studies (eventually including his work on Taylor’s “Fatalism”), but with misgivings: he hoped he would ultimately be bold enough to give up philosophy for literature. His close friend Mark Costello, who roomed with him at Amherst (and also became a novelist), told me that the shift was daunting for Wallace. “The world, the reference, of philosophy was an incredibly comfortable place for young Dave,” he said. “It was a paradox. The formal intellectual terms were cold, exact, even doomed. But as a place to be, a room to be in, it was familiar, familial, recognized.” Fiction, Costello said, was the “alien, risky place.”

Wallace’s solution was to pursue both aims at once. His senior year, while writing the honors thesis in philosophy, he also completed an honors thesis in creative writing for the English Department, a work of fiction nearly 500 pages long that would become his first novel, The Broom of the System, which was published two years later, in 1987. Even just the manual labor required to produce two separate theses could be overwhelming, as suggested by an endearingly desperate request Wallace made in a letter to William Kennick, the Amherst professor who had taught his Wittgenstein seminar. “Since you’re on leave,” he wrote, “are you using your little office in Frost library? If not, does it have facilities for typing, namely an electrical outlet and a reasonably humane chair? If so, could I maybe use the office from time to time this spring? I have a truly horrifying amount of typing to do this spring—mostly for my English thesis, which has grown Blob-like and out of control—and my poor neighbors here in Moore are already being kept up and bothered a lot.”

Despite the heavy workload, Wallace managed to produce a first draft of the philosophy thesis well ahead of schedule, before winter break of his senior year, and he finished both theses early, submitting them before spring break. He spent the last month or so of the school year reading other students’ philosophy theses and offering advice. “He was an incredibly hard worker,” Willem deVries, a philosopher now at the University of New Hampshire and the principal adviser on Wallace’s thesis, told me, recalling the bewilderment with which he and his fellow professors viewed Wallace. “We were just shaking our heads.” By the end of his tenure at Amherst, Wallace decided to commit himself to fiction, having concluded that, of the two enterprises, it allowed for a fuller expression of himself. “Writing The Broom of the System, I felt like I was using 97 percent of me,” he later told the journalist David Lipsky, “whereas philosophy was using 50 percent.”

Given his taste for experimental fiction, however, Wallace didn’t assume, as he prepared to leave Amherst, that he would be able to live off of his writing. He considered styling himself professionally after William H. Gass, the author of Omensetter’s Luck (a novel Wallace revered), who had a Ph.D. in philosophy from Cornell and whose “day job” was teaching philosophy at Washington University in St. Louis. Wallace toyed with applying to Washington University for graduate school so he could observe Gass firsthand. But in the end, he chose to attend the University of Arizona for an M.F.A. in creative writing, which he completed in ‘87, the same year he published The Broom of the System and sold his first short-fiction collection, Girl with Curious Hair.

Even with those literary successes, however, Wallace soon suffered another serious crisis of confidence, this time centered around his fiction. He later described it as “more of a sort of artistic and religious crisis than it was anything you might call a breakdown.” He revisited the idea that philosophy could provide order and structure in his life, and that year he applied to graduate programs at Harvard and Princeton Universities, ultimately choosing to attend Harvard.”The reason I applied to philosophy grad school,” he told Lipsky, “is I remembered that I had flourished in an academic environment. And I had this idea that I could read philosophy and do philosophy, and write on the side, and that it would make the writing better.”

Wallace started at Harvard in the fall of ‘89, but his plan quickly fell to pieces. “It was just real obvious that I was so far away from that world,” he went on. “I mean, you were a full-time grad student. There wasn’t time to write on the side—there was 400 pages of Kant theory to read every three days.” Far more worrisome was the escalation of the “artistic and religious crisis” into another wave of depression, this time bordering on the suicidal. Late that first semester, Wallace dropped out of Harvard and checked into McLean Hospital, the storied psychiatric institution nearby in Massachusetts. It marked the end of his would-be career in philosophy. He viewed the passing of that ambition with mixed emotions. “I think going to Harvard was a huge mistake,” he told Lipsky. “I was too old to be in grad school. I didn’t want to be an academic philosopher anymore. But I was incredibly humiliated to drop out. Let’s not forget that my father’s a philosophy professor, that a lot of the professors there were revered by him. That he knew a couple of them. There was just an enormous amount of terrible stuff going on. But I left there and I didn’t go back.”

III. “INTERPRET-ME fiction”

Though Wallace abandoned it as a formal pursuit, philosophy would forever loom large in his life. In addition to having been formative for his cast of mind, philosophy would repeatedly crop up in the subject matter of his writing. His essay “Authority and American Usage,” about the so-called prescriptivist/descriptivist debate among linguists and lexicographers, features an exegesis of Wittgenstein’s argument against the possibility of a private language. In Everything and More, his book about the history of mathematical ideas of infinity, his guiding insight is that the disputes over mathematical procedures were ultimately debates about metaphysics—about “the ontological status of math entities.” His article “Consider the Lobster” begins as a journalistic report from the annual Maine Lobster Festival but soon becomes a philosophical meditation on the question, “Is it all right to boil a sentient creature alive just for our gustatory pleasure?” This question leads Wallace into discussions about the distinction between pain and suffering; about the relation between ethics and (culinary) aesthetics; about how we might understand cross-species moral obligations; and about the “hard-core philosophy”—the “metaphysics, epistemology, value theory, ethics”—required to determine the principles that allow us to conclude even that other humans feel pain and have a legitimate interest in not doing so.

Those are just explicit examples. Wallace’s writing is full of subtler philosophical allusions and passing bits of idiom. In Infinite Jest, one of the nine college-application essays written by the precocious protagonist, Hal Incandenza, is “Montague Grammar and the Semantics of Physical Modality”—a nod to Wallace’s own philosophy thesis. A story in his short-fiction collection Oblivion, “Philosophy and the Mirror of Nature,” shares its title with the 1979 book of anti-epistemology by the philosopher Richard Rorty. The story “Good Old Neon” invokes two conundrums from mathematical logic, the Berry and Russell paradoxes, to describe a psychological double bind that the narrator calls the “fraudulence paradox.” At the level of language, Wallace’s books are peppered with phrases like “by sheer ontology,” “ontologically prior,” “in- and extensions,” “antinomy,” “techne.”

Perhaps the most authentically philosophical aspect of Wallace’s nonfiction, however, is the sense he gives his reader, no matter how rarefied or lowly the topic, of getting to the core of things, of searching for the essence of a phenomenon or experience. His article on the tennis player Roger Federer delves into the central role of beauty in the appreciation of athletics. His antic recounting of a week-long Caribbean cruise penetrates beneath the surface of his own satirical portrait to plumb a set of near-existential issues—freedom of choice, the illusion of freedom, freedom from choice—that he saw lurking at the heart of modern American ideas of entertainment. “I saw philosophy all over the place,” DeVries, his former professor, said of Wallace’s writings. “It was even hard to figure out how to single it out. I think it infuses a great deal of his work.”

As far as Wallace’s fiction is concerned, the most philosophically intriguing text is the novel he wrote when his own philosophical efforts were most intense: The Broom of the System. In some way—though it’s not obvious at first in what way—the book is clearly supposed to be “about” Wittgenstein’s philosophy. The plot follows a young switchboard operator named Lenore Stonecipher Beadsman as she searches for her great-grandmother, a former student of Wittgenstein’s at Cambridge University who has disappeared from her nursing home. Gramma Beadsman had been a dominant and intellectually bullying figure in Lenore’s life, forever hinting that she would prove to Lenore “how a life is words and nothing else”—a haunting suggestion that seems to be the source of Lenore’s persistent anxiety that she herself might be just a character in a novel. Gramma has left behind in her desk drawer several objects that are potential clues to her disappearance, including a copy of Philosophical Investigations.

The Broom of the System takes its title from a philosophical lesson that Gramma Beadsman once imparted to Lenore’s younger brother, LaVache. While sweeping the kitchen floor with a broom, Gramma asked LaVache “which part of the broom was more elemental, more fundamental,” the handle or the bristles? LaVache replied that the bristles are the essence of a broom. But Gramma corrected him, insisting that the answer depends on the use to which the broom is being put: if you want to sweep, the bristles are the essence—in effect, the meaning—of the broom; if you want, say, to break a window, its essence is the handle. “Meaning as use,” Gramma intoned. “Meaning as use.” The reader familiar with Wittgenstein will recognize in Gramma’s words the governing slogan of his late philosophy: “the meaning of a word,” he wrote in the Investigations, “is its use in the language.”

In his letter to Lance Olsen, Wallace revealed that Gramma Beadsman was “based loosely” on Alice Ambrose, “a very old former Smith professor who lived near me”—Smith College is part of the Five Colleges consortium to which Amherst belongs—”and had been one of the students whose notes were comprised by Witt’s Blue and Brown books.” Though Wittgenstein’s late philosophy was published posthumously, parts of it were available during his lifetime in the form of two sets of students’ notes known as the “Blue Book” and the “Brown Book”; the “Brown Book” notes were dictated to Ambrose and another student, Francis Skinner, during classes at Cambridge in 1934–35. As the great-granddaughter of Alice Ambrose/Gramma Beadsman, Lenore, like Wallace himself, is the descendent of a philosopher with an amanuensis-like connection to Wittgenstein: James Wallace’s mentor, Norman Malcolm, served as the sounding-board and assistant for the writing of Wittgenstein’s final philosophical work, On Certainty.

By the time Wallace started writing Broom, he had developed a serious interest in Wittgenstein’s late philosophy. As his relationship with technical philosophy cooled, he became increasingly curious about approaches to philosophy that, for all their differences with one another, were united in their opposition to the kind of work with which he previously self-identified. He was intrigued not only by Wittgenstein’s late philosophy but also by J. L. Austin’s “ordinary language” philosophy and even Jacques Derrida’s radical conception of philosophy as a metaphysically arrogant form of literature.

Those new curiosities about the relation of language to reality mark another point of connection between Wallace and his character Lenore, who worries that language suffuses reality to the point of constituting it. Indeed, at the simplest level, Lenore just is Wallace, and The Broom of the System is just a fictionalized retelling—a “little self-obsessed bildungsroman,” Wallace called it—of the intellectual struggles he was then undergoing, struggles not only between philosophy and literature but also between technical philosophy and its philosophical alternatives. “Think of The Broom of the System,” he told McCaffery, “as the sensitive tale of a sensitive young WASP who’s just had this mid-life crisis that’s moved him from coldly cerebral analytic math to a coldly cerebral take on fiction and Austin-Wittgenstein-Derridean literary theory.” This transformation, he explained, had a disturbing side effect, shifting the young WASP’s “existential dread from a fear that he was just a 98.6-degree calculating machine to a fear that he was nothing but a linguistic construct.” Lenore, with her apprehension that she may be nothing more than a character in a novel, is giving voice to Wallace’s own anxieties about crossing into a wholly new relationship with language.

Understanding The Broom of the System as an autobiographical roman à clef is a useful first step in grasping Wallace’s literary-philosophical aims, but his engagement with Wittgenstein’s philosophy was a more profound and lasting affair than that reading alone suggests. In both his early and his late work, Wittgenstein addressed the doctrine of solipsism, the philosophical position that holds (in its most radical form) that nothing exists apart from your own mind and mental states. Like fatalism, solipsism is an extreme and counterintuitive view that is nonetheless difficult to disprove. Also like fatalism, it was an idea that bewitched and bothered Wallace, absorbing his intellect and artistic imagination and becoming a lifelong fascination. In his interview with McCaffery, Wallace said that “one of the things that makes Wittgenstein a real artist to me” is the handling of solipsism in his work. In Broom, Wallace sought to do some measure of novelistic justice to this aspect of Wittgenstein’s thought.

Broom, then, belongs to the genre of the novel of ideas—books like Voltaire’s Candide and Jean-Paul Sartre’s Nausea, which all but instruct the reader to interpret them in light of certain schools of thought. (Candide is usually read as a parody of Leibnitz’s metaphysics, Nausea as a vision of Sartre’s existentialism.) In his essay “The Empty Plenum,” published in 1990, Wallace called this genre of writing “INTERPRET-ME fiction” and argued that it had a special role to play in the life of the mind. As he knew from chasing the “click” in math and technical philosophy, there are areas of inquiry that might seem remote from the concerns of everyday life but that can, in fact, offer an array of intimate emotional and aesthetic experiences. Even for the reader with an appetite for it, however, a theoretical work can be so intellectually taxing, so draining of one’s mental energies, that what Wallace called the “emotional implications” of the text are overlooked. The novel of ideas is at its most valuable, he contended, not when making abstruse ideas “accessible” or easy to digest for the reader, but rather when bringing these neglected undercurrents to the surface.

Wallace wrote “The Empty Plenum” in Boston in the summer of 1989, as he readied himself to begin the philosophy program at Harvard. The essay is an extended appreciation of David Markson’s novel Wittgenstein’s Mistress (“a work of genius,” in Wallace’s estimation), which came out in ‘88, a year after The Broom of the System, and which was also “about” Wittgenstein’s philosophy. It was an emotional reckoning, as Wallace read it, with the discussion of solipsism in Wittgenstein’s early work. Wallace felt that Markson’s novel had succeeded in uniting literature and philosophy in a way that he, in Broom, had tried but failed to do. (Wallace pronounced Broom “pretty dreadful.”) The circumstances in which Wallace was writing the essay only underscored for him the importance of Markson’s accomplishment. As Wallace prepared to seek a renewed merger of philosophy and fiction in his own life, at Harvard, he celebrated Markson as a novelist who, with the utmost artistry, had already fused the two. In defiance of “the rabid anti-intellectualism of the contemporary fiction scene,” Wallace wrote, Markson had demonstrated the still-vital role of the novel of ideas in joining together “cerebration & emotion, abstraction & lived life, transcendent truth-seeking & daily schlepping.” Markson had delivered on Wallace’s literary-philosophical ideal of “making heads throb heartlike.”

IV. “A kind of philosophical sci-fi”

To understand the philosophical ambitions of Broom it is worth first looking in detail at what Wallace thought Markson had done. Markson’s novel, a work of experimental fiction with a lean style reminiscent of Samuel Beckett, is narrated by a painter named Kate, who appears to be the last person alive and who has been alone on earth for many years by the time the novel opens. Kate doesn’t so much narrate (for she has no audience) as write into the void, tapping out on a typewriter declarative statement after declarative statement in simple paragraphs of just one or two sentences. Unlike many novels of ideas, Wittgenstein’s Mistress doesn’t feature cerebral characters or lofty discussions. Though Kate makes highbrow allusions, her grasp of history and literature and philosophy is idiosyncratic and shaky. As Wallace noted, in Kate’s hands intellectual ideas are “sprayed, skewed, all over the book.”

After many years roaming the earth, futilely looking for anyone else, Kate has retired to a beach house, where she is writing out her thoughts. She does so with a peculiar controlled indirection, free-associating but looping back again and again to a recurring set of personal preoccupations—compulsively trying to keep straight the memory of what has been lost, organizing and reorganizing scattered memories of her own life and her piecemeal knowledge of the world to which she once belonged:

I do remember sitting one morning in an automobile with a right-hand drive and watching Stratford-on-Avon fill up with snow, which must surely be rare.

Well, and once that same winter being almost hit by a car with nobody driving it, which came rolling down a hill near Hampstead Heath.

There was an explanation for the car coming down the hill with nobody driving it.

The explanation having been the hill, obviously.

That car, too, had a right-hand drive. Although perhaps that is not especially relevant to anything.

The possibility increases that Kate’s narration is unreliable, that she is mentally unhinged, as it becomes clearer that the onset of her peculiar experience of the world coincided with a profound personal loss. The book imparts a double-layered feeling of loneliness and isolation: Kate’s is the voice of a writer trapped not only inside her own head but also inside a world that now exists only through her own continual reconstructing of it. The text she types, Wallace wrote, “is itself obsessed & almost defined by the possibility that it does not exist, that Kate does not exist.”

What does any of this have to do with Wittgenstein? Part of the achievement of Markson’s novel, one of the ways in which it avoids the pitfalls of many novels of ideas, is that it doesn’t require any understanding of Wittgenstein. The novel operates on its own terms. But the allusion to Wittgenstein in its title, its repeated citation of the first sentence of the Tractatus (“The world is all that is the case”), and its stylistic affinity with that book (the Tractatus is also composed of short aphoristic paragraphs) all invite the reader versed in philosophy to wonder what Markson is up to. “This isn’t a weakness of the novel,” Wallace stressed. “Though it’s kind of miraculous that it’s not.”

Wallace had read the Tractatus, of course (he wrote to Lance Olsen that he thought its first sentence was “the most beautiful opening line in western lit”). He knew that Wittgenstein’s book presented a spare and unforgiving picture of the relations among logic, language, and the physical world. He knew that the puzzles solved and raised by the book were influential, debatable, and rich in their implications. But as a flesh-and-blood reader with human feelings, he also knew, though he had never articulated it out loud, that as you labored to understand the Tractatus, its cold, formal, logical picture of the world could make you feel strange, lonely, awestruck, lost, frightened—a range of moods not unlike those undergone by Kate herself. The similarities were not accidental. Markson’s novel, as Wallace put it, was like a 240-page answer to the question, “What if somebody really had to live in a Tractatusized world?” Pronouncing the novel “a kind of philosophical sci-fi,” Wallace explained that Markson had staged a human drama on an alien intellectual planet, and in so doing he had “fleshed the abstract sketches of Wittgenstein’s doctrine into the concrete theater of human loneliness.”

V. “The loss of the whole external world” The particular form of “human loneliness” to which Wallace was attuned was the sense of seclusion suggested by solipsism. Kate, Markson’s narrator, seems to be in a situation like this, her world constituted entirely by her mental states. She shares this predicament with the traditional metaphysical subject of epistemology—the knowing consciousness, the “I” of Descartes’s “I think, therefore I am”—who begins his intellectual journey trapped in his own mind, concerned that everything might just be a figment of his imagination (though he ultimately builds his way out of those confines to reach the external world). Wittgenstein, in the Tractatus, runs into the concern that his argument leads to solipsism—and his striking response is to agree, after a fashion, that it does. “There’s a kind of tragic fall Wittgenstein’s obsessed with,” starting with the Tractatus, Wallace explained to McCaffery. “I mean a real Book-of-Genesis-type tragic fall. The loss of the whole external world.”

How did Wittgenstein get to this point? The Tractatus is concerned with a disarmingly basic question: How is language possible? When we consider the world around us, everything seems to interact with everything else causally, in accordance with the laws of nature. The exception is a certain strange thing we call language, which somehow manages to interact with other things in the world in an entirely different way: it represents them meaningfully. The ability to represent things allows us to communicate, enables us to deal with things that are not actually presentto us, and provides the fabric of our mental life, our daily thoughts. But how is it, exactly, that language produces meaning?

In the Tractatus, Wittgenstein argues that for words to represent things, for sentences to stand for states of affairs, language and reality have to share something in common. To explain what this commonality is, he introduces his so-called picture theory of meaning. An ordinary spoken or written sentence, he contends, when properly analyzed or disassembled into its component bits, reveals an elementary structure of logical parts and factual parts. This elementary structure, he argues, literally pictures reality: objects in the world correlate with the words in the sentence, and the relations among and between objects in the world correlate with the relations among and between the words in the sentence. A sentence has a certain elementary structure; things in the world can stand to one another in a certain structure; the identity of these two structures simply is meaning. A meaningful sentence depicts a possible state of affairs in the world; a meaningful and true sentence depicts an actual state of affairs in the world; anything in language that does not depict a possible state of affairs—that is, anything that does not depict possible fact—is, strictly speaking, meaningless.

Wittgenstein draws from the picture theory of meaning some arresting philosophical conclusions. The Tractatus regards as nonsensical, as literally meaningless, any claim that cannot be reduced to discrete facts about things in the world—for instance, any statements about ethics or aesthetics (“goodness” and “beauty” don’t refer to actual things or properties). Another such type of nonsense, according to Wittgenstein, are metaphysical statements, claims about the supernatural, say, or the nature of the world as a whole. How language relates to reality—the very subject of the Tractatus—is itself, however, a concern about the world as a whole. This is the central irony of the Tractatus: its own claims are, strictly speaking, meaningless. They can be used only to try to show, but never to state, anything true. (This is the source of Wittgenstein’s famous parting image of his book as a ladder that his reader must “throw away” after “he has climbed up it.”)

For Wallace, the most disquieting feature of the Tractatus was its treatment of solipsism. Toward the end of the book, Wittgenstein concludes, “The limits of my language mean the limits of my world.” This is a natural corollary of the picture theory of meaning: Given that there is a strict one-to-one mapping between states of affairs in the world and the structure of sentences, what I cannot speak of (that is, what I cannot meaningfully speak of) is not a fact of my world. But where am “I” situated in this world? By “I,” I don’t mean the physical person whom I can make factual reports about. I mean the metaphysical subject, the Cartesian “I,” the knowing consciousness that stands in opposition with the external world. “Where in the world,” Wittgenstein writes, “is a metaphysical subject to be found?”

On the one hand, the answer is nowhere. Wittgenstein can’t make any sense of the philosophical self—any talk of it is, strictly speaking, nonsense. On the other hand, Wittgenstein can get some purchase on this question. He draws an analogy between the “I” (and the external world) and the eye (and the visual field): Though I cannot see my own eye in my visual field, the very existence of the visual field is nothing other than the working of my eye; likewise, though the philosophical self cannot be located in the world, the very experience of the world is nothing other than what it is to be an “I.” Nothing can be said about the self in Wittgenstein’s philosophy, but the self is mademanifest insofar as “the world is my world”—or, as Wittgenstein more strikingly phrases it, “I am my world.” This, he declares, is “how much truth there is in solipsism.”

“I am my world” is what Wallace had in mind when he spoke of “the loss of the whole external world” in the Tractatus. There is no difference, ultimately, for Wittgenstein between solipsism and realism (solipsism “coincides with pure realism,” he writes). For Wallace, this was a harrowing equation, the dark emotional takeaway of the Tractatus’s severe anti-metaphysics. This was also, for Wallace, what Markson had rendered imaginatively in his novel. Without ever raising these ideas explicitly, Markson had conveyed them with a special kind of clarity. Wittgenstein’s Mistress, by echoing the Tractatus’s brusque, dreamlike sentences and placing Kate in a cold, lonely, self-as-world cosmos, had managed, as Wallace put it, to “capture the flavor both of solipsism and of Wittgenstein.” What’s more, Wallace felt Markson had done something that even Wittgenstein hadn’t been able to do: he humanized the intellectual problem, communicating “the consequences, for persons, of the practice of theory; the difference, say, between espousing ‘solipsism’ as a metaphysical ‘position’ & waking up one fine morning after a personal loss to find your grief apocalyptic, literally millennial, leaving you the last and only living thing on earth.” That was something only fiction, not philosophy, could do.

Solipsism, sometimes discussed as a doctrine but also evoked as a metaphor for isolation and loneliness, pervades Wallace’s writing. “Plainly, Dave, as a guy and a writer, had a lifelong horror/fascination with the idea of a mind sealed off,” Mark Costello told me. “His stories are full of sealed-off people.” The self-obsessing narrator of “Good Old Neon,” who has committed suicide and addresses the reader from beyond the grave, says “you’re at least getting an idea, I think, of what it was like inside my head,” of “how exhausting and solipsistic it is to be like this.” The high-school students at the tennis academy in Infinite Jest wrestle with the question, “how we can keep from being 136 deeply alone people all jammed together?”—a problem that one of them diagnoses in intellectual terms (“Existential individuality, frequently referred to in the West. Solipsism”) and another in emotional ones (“In a nutshell, what we’re talking about here is loneliness”). The novelist Jonathan Franzen, one of Wallace’s close friends, has said that he and Wallace agreed that the fundamental purpose of fiction was to combat loneliness. The paradox for Wallace was that to be a writer called for spending a lot of time alone in one’s own head, giving rise to the feeling, as he wrote in “The Empty Plenum,” “that one’s head is, in some sense, the whole world, when the imagination becomes not just a more congenial but a realer environment than the Big Exterior of life on earth.”

VI. “ The single most beautiful argument against solipsism that’ s ever been made.”

Could solipsism be overcome? In The Broom of the System, Norman Bombardini, a very wealthy and very overweight man who owns the building in which Lenore works, bemoans what he calls “the Great Horror”: the prospect of “an empty, rattling personal universe, one where one finds oneself with a Self, on one hand, and vast empty lonely spaces before Others begin to enter the picture at all, on the other.” He devises a solution, a kind of spoof of the Tractatus’s line “I am my world,” which is to keep eating until he grows to infinite size, making himself coextensive with the world. (He calls the scheme “Project Total Yang.”) Bombardini is only a minor character in the novel, and fittingly so, for the bulk of The Broom of the System is concerned not with the solipsism of early Wittgenstein but rather with the philosophy of the later Wittgenstein—who roundly rejected solipsism. Just as Markson conjured the solipsism of the Tractatus into an artistic creation, so too did Wallace hope to summon, in Broom, the anti-solipsistic worldview of Philosophical Investigations.

The Investigations offers a conception of language that is diametrically opposed that of the picture theory of the Tractatus. In Wittgenstein’s early work, language is something sublime, logical, abstract—something with a defining structure or essence that, if you think hard enough, you can puzzle out in your head. In the Investigations, by contrast, language is seen as a messy human phenomenon, part of social reality—a rich variety of everyday practices that you figure out the way a child does, by publicly engaging in them, getting the hang of the unspoken rules by which communities use them. The shift in imagery is from language as a picture to language as a tool. This is the point of the Wittgensteinian mantra “meaning as use”: If you want to understand the meaning of a word or phrase or gesture, you don’t try to figure out what it represents; you try to figure out how to use it in real life. Wittgenstein called the rule-governed social practices that determine meaning “language games.”

As Wallace was delighted to discover when he immersed himself in the Investigations later in college, the implications of this view for solipsism are potentially devastating. Given Wittgenstein’s conception of language as a public phenomenon, whereby words get their meaning only by virtue of their shared use, what are we to make of the notion of a strictly private language, the voice of a solipsistic “I” who is speaking only to himself, in his own unique tongue, reporting private sensations and entertaining private thoughts in an otherwise barren world—the voice of a person living entirely in his own head? Wittgenstein’s answer was that this idea, though seemingly viable, at least as a thought experiment, is in fact incoherent. The meaning of words is their use; the use of words is a matter of following rules; and following rules is entirely a social affair. There cannot be thought apart from the use of language—and language can operate only within a set of social practices. Thus there is no private thought without a corresponding public reality. “An ‘inner process,’ ” as Wittgenstein put it, “stands in need of outward criteria.” To phrase it in Cartesian terms: I think, therefore I am part of a community of others.

Wallace told McCaffery that Philosophical Investigations was “the single most beautiful argument against solipsism that’s ever been made.” Though the anti-private-language argument has been extraordinarily controversial, Wallace heralded it as though it were an indisputable mathematical proof. “The point here,” he wrote in “Authority and American Usage,” while giving a summary of Wittgenstein’s argument, “is that the idea of a private language, like private colors and most of the other solipsistic conceits with which this reviewer has at various times been afflicted, is both deluded and demonstrably false.” Solipsism was dead. Loneliness—at least that image of loneliness—was an illusion.

The defeat of solipsism was half of what Wallace sought to capture in Broom. But while Wittgenstein may have “solved” solipsism for Wallace, there was a catch—a final entangling conundrum with its own frightening implications—which Wallace also wanted to convey. On its face, the account of language in the Investigations seems pleasantly, reassuringly everyday: language is an ordinary, familiar, social, custom-bound human activity. But in other respects the account is quite extreme. Because all language and thought take place inside some language game or other, there is no transcendent, non-language-game standpoint from which you can step back, as it were, and see if any language game is better than any other—if one of them, for instance, does a better job of mirroring reality than another. Indeed, the question of whether any language game accurately represents reality can be asked only within some other language game, which operates according to its own set of nonevaluable conventions. In his early work Wittgenstein was in the business of stepping back from language, appraising its relation with reality, and pronouncing which uses connected us with something real and which did not; the Investigations is in another business altogether, describing without judging, merely “assembling reminders for a purpose,” in Wittgenstein’s phrase.

In Wallace’s view, Wittgenstein had left us, again, without the possibility of contact with the outside world. As he told McCaffery, the Investigations “eliminated solipsism but not the horror.” The only difference between this new predicament and that of the Tractatus was that rather than being trapped alone in our private thoughts, we were trapped together, with other people, in the institution of language. This was warmer than solipsism, but, as another form of being sealed-off from reality, it was cold comfort. Explaining this disheartening realization, Wallace said that “unfortunately we’re still stuck with the idea that there’s this world of referents out there that we can never really join or know because we’re stuck in here, in language, even if we’re at least all in here together.”

In The Broom of the System, these two dueling emotional reactions—the fear of being trapped in language and the relief that at least we’re all trapped in it together—are given playful expression. Lenore suffers from a fear, as she explains to her psychiatrist, that Gramma Beadsman is right that “there’s no such thing” as “extra-linguistic anything.” (Wallace’s metafictional joke is that, for Lenore, as a character in a novel, there really isn’t any reality other than language.) Lenore’s boyfriend, a magazine editor named Rick Vigorous, soothes her throughout the book by compulsively telling her stories. Each of his stories is a not-so-thinly veiled allegory of the problems in their relationship, so that, even within the confines of the novel, Lenore and Rick become characters joined together in a reality constituted entirely by language. In the novel’s climactic scene, a televangelist-charlatan named Reverend Sykes provides another image of this same double bind: escaping loneliness together in a language game, but sealed off from a higher reality. He asks the members of his TV audience to lay their hands on their TV screens in unison in order to commune with God—to join together in what he calls a “game” that will give everyone the consoling impression of making contact, together, with the ultimate transcendent referent. “So friends,” Sykes says, “laugh if you will, but tonight I have a game for us to play together. A profoundly and vitally important game for us to play together tonight.” His patter culminates in a three-sentence exhortation, the lines of which invoke the ideas of “meaning as use,” language games, and the struggle against loneliness: “Use me, friends. Let us play the game together. I promise that no player will feel alone.” Compared to the artful techniques of Markson’s novel, these devices may seem clunky, but the intellectual aspiration was much the same.

It is worth noting that, in his discussions of Markson, Broom, and solipsism, Wallace was engaging throughout in what you might call a “strong misreading” of Wittgenstein’s work. His explications of Wittgenstein’s philosophy are not always convincing or strictly true. Highly questionable, for instance, is his assertion of what he called “the postmodern, poststructuralist” implications of the Investigations, which entail that we can’t make true claims about the real world (a popular reading of Wittgenstein that many scholars hotly dispute). More straightforwardly wrong is Wallace’s claim that Wittgenstein shared Wallace’s own horror of the picture of the world in the Tractatus. Wallace told McCaffery that the reason Wittgenstein “trashed everything he’d been lauded for in the Tractatus” and developed the philosophy of the Investigations was that he “realized that no conclusion could be more horrible than solipsism.” Wallace also contended, in “The Empty Plenum,” that the impoverished role granted to ethics, aesthetics, and spiritual values in the Tractatus was “a big motivation” for its disavowal.

In truth, however, the biographical literature suggests that Wittgenstein was perfectly at ease with the solipsism of the Tractatus, as well as oddly, even mystically consoled by its suggestion that ethical, aesthetic, and spiritual truths are unutterable. As for the development of the late philosophy, it seems to have had its origins not in a fear of solipsism but rather in two deeply resonant objections: a technical criticism that the British mathematician Frank Ramsey made in 1923 about the Tractatus’s treatment of the matter of “color-exclusion” and a playful challenge, posed by the Italian economist Piero Saffra, that Wittgenstein provide the “logical form” of a meaningful hand gesture.

It’s possible that Wallace’s own anxieties about being “trapped” in his own head colored or confused his reading of Wittgenstein—that he projected them, in philosophical terms, onto the Tractatus and the Investigations, resulting in an overemphasis on solipsism and giving Wittgenstein’s treatment of the doctrine an alarmist, even hysterical cast. But given Wallace’s otherwise sure-handed feel for philosophical texts, it seems likely that his distortions were at least in part intentional, offered in the service of artistic and emotional “truths.” That would certainly be consistent with the ideal of fictionalized philosophy that he strove for in Broom and venerated in Wittgenstein’s Mistress—a kind of writing that blended scholarly command and poetic reimagining.





Whatever the explanation for his preoccupation with solipsism in Wittgenstein, Wallace never abandoned his fixation on sealed-off people. Few readers of Infinite Jest will forget the lonely fate of the Hal Incandenza, who becomes so alienated from the world that his speech becomes unintelligible to others, or the lifeless zombiehood that befalls anyone who watches the novel’s eponymous film, which is so entertaining that its viewer becomes incapable of doing anything other than watch it. But Mark Costello pointed out to me an important irony: for someone as obsessed with isolation as Wallace, he was “obviously a social novelist, a novelist of noticed details, on a near-encyclopedic scale.” Where other novelists dealing with solipsism, like Markson and Beckett, painted barren images with small compressed sentences, Costello observed, “Dave tackled the issue by massively overfilling his scenes and sentences to comic bursting”—indeed to the point of panicked overstimulation. There was a palpable strain for Wallace between engagement with the world, in all its overwhelming fullness, and withdrawal to one’s own head, in all its loneliness. The world was too much, the mind alone too little. “You can’t be anything but contemptible living for yourself,” Costello said, summing up the dilemma. “But letting the world in—that sucks too.”

It’s not exactly what you’d call an intellectual conundrum. But it was the lived one.

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