... if indeed Ronald Reagan sees the world as a game of Risk, we might as well be making games that ... teach this new generation of little Ronnies out there that the world is not necessarily a zero-sum game...
Starts off as a book review, then takes a turn toward game design and commentary on society.
Merry Thanksgiving, native American day of mourning. This is a review of a book called The Evolution of Cooperation, by Robert Axelrod, a political scientist and game theorist. The back cover of the book includes the following quotes - "I never expected to find wisdom or hope for the future of our species in a computer game, but here it is, in Axelrod's book. Read it." - Lewis Thomas, M.D. (Read his books too.) "When I read The Evolution of Cooperation in draft form, I scribbled all over my copy: 'Incredible!' 'Amazing!' 'Weird!' 'Fantastic!' 'Fascinating!' 'Elegant!' 'Great!' I guess that tells you what I genuinely think of this book." - Douglas Hofstadter, author of Godel, Escher, Bach: An Eternal Golden Braid (Another good read, at least for skipping around in.) These guys aren't exaggerating, plus the book's relatively short and easy reading. Here's how I heard about the book - First, someone who read my War & Games article in Sept. Creative Computing sent me a copy of a review that a friend of his wrote about the book. Then another reader of the article, and president of an educational software company, sent an Apple program he had written which, based on Axelrod's book, allows you to play the Prisoner's Dilemma and vary the computer's strategy. And then a group called Computer Professionals for Social Responsibility wrote to say that a group had formed in Berkeley to study and write a paper about applying the Prisoner's Dilemma model to attempts to understand and redirect the arm's race. (These meetings are every other Thursday in Berkeley, starting Nov. 29. Contact me if you're interested.) So let me talk a bit about what's in the book and then I'll discuss why it might be of interest to game designers. The essence of life often seems to be paradox, and the Prisoner's Dilemma is an elegant mathematical model of one basic type of paradox, "in which what is best for each person individually leads to mutual defection, whereas everyone would have been better off with mutual cooperation." Axelrod uses the theory to examine the uses of cooperation and competition in warfare, business, Congress, and biological systems. The basic dilemma is (quoting from the inside liner): "How can cooperation emerge among self-seeking individuals when there is no central authority to police their actions? It is a question that has troubled philosophers and statesmen for hundreds of years; its importance has never been greater than in today's world of nuclear weapons." Axelrod manages to answer this question for the 2x2 Prisoner's Dilemma and to suggest the implications this solution has for the real world. He started by organizing computer tournaments to which he invited computer hobbyists and professional game theorists to submit their favorite strategy for playing the Prisoner's Dilemma. Competing programs included 1) a program based on 'outcome maximization', 2) Random, 3) one that cooperates initially but then defects forever after the other side's first defection, 4) "a sneaky rule that tries to get by with an occasional defection," 5) a program that is designed to "look for softies, but is prepared to back off if the other player shows it won't be exploited", and 6) a program that "first seeks to establish a mutually rewarding relationship with the other player, and only then does it cautiously try to see if it will be allowed to get away with something." The winning entry was the shortest and simplest of all the programs - called Tit for Tat, it says to start with cooperation and then do what the other side did on the last round. While this is not necessarily the winning strategy independent of the environment, it is fairly robust, due to four properties: 1) It is 'nice' - it avoids unnecessary conflict as long as the other player does. 2) It is retaliatory - it responds immediately to provocation. 3) It is forgiving - it backs off from retaliation as soon as the other player stops provoking it. 4) It is clear - the other side can easily predict its behavior, and adapt to it by cooperating. Tit for Tat is not capable of beating any of the other strategies one on one, and yet it does best in the tournament because it gets the other strategies to cooperate with it. The moral here for success in non-zero sum games is - don't be envious. Don't compare your score to your opponent's score, but to how well someone else could be doing in your situation. The key factor to the success of a strategy such as this is the shadow of the future - the importance of future relations between the same individuals. The theory gets extended to show how the different strategies will evolve in time (including a graph of how an initially successful non-nice rule soon becomes extinct as a result of the extinction of the unsuccessful rules it was exploiting.) Axelrod proves a number of theorems, such as one which states that a society of 'meanies' (who always defect) can resist an invasion by any other strategy which invades 1 by 1 (but a small cluster of the other strategy can invade relatively easily by surviving off of their cooperations with each other.) However a society made up of a 'nice' strategy can be resistant to invasion by 'meanies', even in a cluster. Then he extends the theory to territorial patterns (of nations, businesses, birds, etc.) and shows graphs of how different strategies can evolve spatially. Why do I mention all this? Well, it's that time of year when some of us are finishing up our games and starting to think about new ones, and I want to nudge those new games in certain directions. I'd like to see more games that allow the player to explore the continuum of cooperation and competition. This was very successful in Joust, Rip-Off, and a few other games. And I'd like to see more 2-player games in general - 2 player Marble Madness is, strictly speaking, a competitive game, but it give you a range of competitiveness from hard-core knock-the-other-guy-over-the-edge, to just racing against the clock. And it might be nice to have games with less emphasis on scores, or no scores at all, or seeing only your score and not the other player's, or having a score which is the sum of your score and the opponent's score. Of course I'd also like to see more games like Whack- A-Mole (why were there no Whack-A-Moles in the auction, that's what I'd like to know.) If indeed people form attitudes about life from the games they play, and if indeed Ronald Reagan sees the world as a game of Risk, we might as well be making games that, in a very non-educational way, teach this new generation of little Ronnies out there that the world is not necessarily a zero-sum game, that there are ways to play the game so that both sides win. I think there are sparks in this book which could ignite a great game idea. The 2-player Prisoner's Dilemma itself is rather boring to play, although some fun and visually interesting patterns might result from the 2-d territorial evolution version of the game. The real interest is in the meta-game, the insights from which could be (and have been) applied to a variety of situations. I have some thoughts on the subject, which I would be glad to discuss with anyone interested, as soon as we all have more time (i.e., January.) The book is available for borrowing from me, and for sale in finer bookstores everywhere. Earl
Nov 22, 1984