[In his latest 'Persuasive Games' column, author and game designer Ian Bogost looks at why we should repeal Bushnell's Law and move from 'addiction' to 'catchiness' in our framing of video games.]
Here's a game design aphorism you've surely heard before: a game, so it goes, ought to be "easy to learn and hard to master."
This axiom is so frequently repeated because it purports to hold the key to a powerful outcome: an addicting game, one people want to play over and over again once they've started, and in which starting is smooth and easy.
It's an adage most frequently applied to casual games, but it is also used to describe complex games of deep structure and emergent complexity.
In the modern era, this familiar design guideline comes from coin-op. The aphorism is often attributed, in a slightly different form, to Atari founder Nolan Bushnell. In his honor, the concept has earned the title "Bushnell's Law" or "Nolan's Law":
"All the best games are easy to learn and difficult to master. They should reward the first quarter and the hundredth."
Bushnell learned this lesson first-hand when his first arcade cabinet Computer Space, a coin-op adaptation of the PDP-1 ur-videogame Space War, failed to become a commercial success.
Computer Space was complex, with two buttons for ship rotation, one for thrust, and another one for fire. While the same layout would eventually enjoy incredible success in the coin-op Asteroids, four identical buttons with different functions was too much for the arcade player of 1971.
Pong was supposedly inspired by this failure, a game so simple it could be taught in a single sentence: Avoid missing ball for high score. It seems so obvious, doesn't it? Games that are easy to start up the first time but also offer long-term appeal have the potential to become classics.
Except for one problem: the "easy to learn, hard to master" concept doesn't mean what you think it does.
Bushnell's eponymous law notwithstanding, the design values of quick pickup and long-term play surely didn't originate with him. Poker is another game that commonly enjoys the description. The same is true for classic board games like Go, Chess, and Othello.
Indeed, the famous board game inventor George Parker apparently adopted a different a version of Bushnell's Law way back in the late 19th century. From Philip Orbanes's history of Parker Bros.:
Each game must have an exciting, relevant theme and be easy enough for most people to understand. Finally, each game should be so sturdy that it could be played time and again, without wearing out.
Note the subtle differences between Bushnell's take and Parker's. Parker isn't especially concerned with the learnability of a game, just that it deal with a familiar topic in a comprehensible way.
A century hence, time is more precious (or less revered), and simplifying the act of learning a game became Bushnell's focus. Still, something more complex than familiar controls or simple instructions is at work here.
Think about it: Pong isn't easy to learn, at all, for someone who has never played or seen racquet sports. Without a knowledge of such sports, the game would seem just as alien as a space battle around a black hole.
As it happens, table tennis became popular in Victorian England around the same time George Parker began creating games seriously. It offered an indoor version of tennis, a popular lawn sport among the upper-class, played with ad-hoc accoutrements in libraries or conservatories.
Both ordinary tennis and its indoor table variety had enjoyed over a century of continuous practice by the time Bushnell and Atari engineer Al Alcorn popularized their videogame adaptation of the sport (itself a revision of two earlier efforts, Willy Higginbotham's Tennis for Two and Ralph Baer's "Brown Box").
Pong offers quick pick-up not because it is easier to learn than Computer Space (although that was also true), but because it draws on familiar conventions from that sport. Or better, Pong is "easy to learn" precisely because it assumes the basic rules and function of a familiar cultural practice.
Familiarity is thus the primary property of the game, not learnability; it is familiarity that makes something easy to learn. It is what makes "Avoid missing ball" make any sense in the first place.
 Philip E. Orbanes, The Game Makers: The Story of Parker Brothers, from Tiddledy Winks to Trivial Pursuit, (Cambridge: Harvard Business School Press, 2003), p. 13. I am grateful to Jesper Juul for bringing this passage to my attention.