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.