The history of video games has been dominated by technological determinism, with scholars tracing a neat line from William Higginbotham’s first game on an oscilloscope screen through more and more complex hardware to 2017’s Nintendo Switch. In this dissertation, I tell the story of video games differently, from the premise that play itself had to be invented as a medium before designers, artists, writers, and engineers could explore its possibilities. While game pieces, accompanying text, and illustrated boards had previously been objects of artistic and commercial manipulation, it was only after the Second World War that the experience of play itself was intentionally shaped through the design of rules, goals, and game mechanics. Games became “graphs of a self-graphing world,” as Mark Seltzer describes them, places where complex systems model and simulate their own workings. This dissertation uses playfulness to track the lineage that extends from the development of avant-garde games in the 1950s and 60s to the establishment of video games as the hegemonic form of play in the 1990s. Playfulness, I argue, involves an interpretive relation to play that can reveal the social commitments, aesthetics concerns, and historical contexts that gave rise to a new culture of games. In particular, I focus on four different kinds of playfulness: replayability, secrecy, trickiness, and fairness. Each of these categories is an interpretive response to an important series of questions that links the pleasures of specific games, to theoretical problems involved in conceptualizing play, and to a wider social world. In playfulness, a formal quality of games—its boundaries, rules, tension, or goals—itself becomes the topic to self-reflexively play with., In each of my four chapters, I trace one strand of an aesthetic genealogy that runs from the mid-twentieth century to the present. In each chapter I begin with an experimental game that seems nearly unplayable because it lacks rules, goals, or mechanics. These works are all by artists associated with Fluxus, which serves as a microcosm of postmodern aesthetics and as an exemplary engagement with game design. These works make explicit the implicit tensions within pervasive discourses of play. Each of my chapters explores a web of intellectual histories where the subtle metaphors of play start to matter and become literal. Fluxus works heighten the contradictions around play as a source of pleasure, and point forward to a new synthesis that I argue is achieved by the video games of the 1990s. These video games successfully internalize the tensions of the earlier avant-garde as a topic of playful uncertainty. Rather than a narrative of technical progress, my dissertation argues that the history of video games to the present has been an ongoing negotiation of play’s aesthetic limits., In Chapter One, “Replayability: Play without Truth,” I stage the intellectual genealogy that brought games into the forefront of postwar thought. In the early twentieth century, games—especially chess—became crucial metaphors for understanding complex interacting systems. Chess showed how linguistic reference could be arbitrary and differential, in much the same way that a pawn’s value depends on its position relative to other pieces. More broadly, games exemplified the inner working of complex systems in disciplines as diverse as anthropology, cybernetics, and psychology. These metaphors set the stage for a dialectical reversal in postwar thought. From postmodern theory to pop-psychology, playfulness was celebrated as an aesthetic of disruption, subversion, agency, self-reflection, change, and irony. Play’s postmodern valences made new media, games, and hypertext fiction a promising subject of study in the 1980s and early 1990s, and the theoretical framework of contemporary game studies owes a direct and unacknowledged debt to this history whose repercussions I explore., Having established a frame for my inquiry, Chapter Two, “Secrecy: Play without Reason” develops a full theory of playfulness. I examine its common definition in psychology and game studies, and argue that they are too narrow to account for the multiple ways that playfulness manifests itself in ordinary life. One classic definition, for instance, holds that playfulness is a compound of spontaneity, manifest joy, and humor. As a counter example, I use this chapter to explore the ways that secrecy can be playful, while simultaneously being ritualized, hidden, and serious. My argument turns on a close reading of Yoko Ono’s use of concealment to create absurd game instructions. Ono’s strategy is to give clear but outlandish rules, while implying that the goal must remain a secret until the game is played. As a result, her work can often obscure the difference between violence, trauma, and play by turning the formal element of game goals into a self-reflexive topic for play. Ono fuses playful and sacred effects, which gives me an opportunity to examine how the two might be separated and specified. I develop a new definition of playfulness as genres of response to the uncertainty that animates games. Using this definition allows me to re-read the forces that motivate a player through the classic platforming game Super Mario World (1990), and display several kinds of unconscious and playful pleasures at work in the game., Chapter Three, “Trickiness: Play without Rules” takes up the theme of uncertainty and explores what happens when uncertainty itself becomes an explicit, self-referential, theme of play. I begin with the rise of chance-based procedures in the art, writing, and music of the 1950s and 1960s, especially in the work of John Cage and his student George Brecht. In an essay titled “Chance-Imagery,” Brecht argues that our ability to think about indeterminacy depends on the equipment of games, such as dice, cards, or roulette wheels that we use to embody chance. In Water Yam (1963), Games & Puzzles (1965), and Deck (1965) Brecht experiments with the limits of conceptualizing uncertainty, and what happens when games refuse to explain their ground rules. Brecht’s aesthetic of trust and wit, where a seemingly impossible situation is salvaged at the last minute, became the guiding pleasure of adventure games. I look closely at a finely crafted example of this genre, King’s Quest VI (1992), to show how video games construct the bounds of their own uncertainty and model the forms of playfulness they expect., I close in Chapter Four, on “Fairness: Play without End,” because it shows how each type of playfulness that I have tracked arises from a social need. Play became a medium, I argue, because game logic is crucial to neoliberalism and postmodernity. Games are the concepts, metaphors, and ideologies without which the present would be unthinkable—whether that means game theory with its rational and strategic models of choice, or the naturalization of risk and precarity. In particular, this chapter examines a discourse of fairness during the civil rights era through the work of Benjamin Patterson. Patterson’s games are miniature acts of civil disobedience that ramp up some small human action until it overwhelms a fragile bureaucratic system. His treatment of social action as a structured game, rather than inalienable rights, leads him to think about the differing capacities and constraints of certain bodies. He studies fairness rather than equality. This same balance comes up repeatedly in modern simulation games, such as SimCity 2000 (1993), but with an emphasis on smooth operation rather than potential disruption. In both cases, fairness shows how a social contradiction or impasse can be worked out through playful strategies of response. , This dissertation advances and expands upon the growing rapport between video game studies and literary criticism. For nearly two decades, the two fields have been addressing the cultural importance of play in near isolation from one another. Literary critics have explored and teased apart a huge range of stylistic qualities that can make texts feel playful, but without a solid framework of what play and games look like as activities in their own right. Game scholars have developed a rich formal tradition for the elements of play and games, which in turn blinds them to the subtler shades of playfulness. While there are clear historical reasons for this divide, there is also a deep continuity between the two traditions. By synthesizing literary methods with game studies, my project identifies an aesthetic and cultural commitment to playfulness that begins after the Second World War and continues into the present. It is part of my broad interest in the aesthetics of play and games in the 20th century, as they get taken up as disciplinary topics, objects of technical development, and models of thought.