Michael Wooldridge is like the teacher you wish you'd had: approachable, able to explain difficult things in simple terms, neither dauntingly highbrow nor off-puttingly cool, and genuinely enthusiastic about what he does. "I love it when you see the light go on in somebody, when they understand something that they didn't understand before," he says. "I find that incredibly gratifying."
He comes across as a regular sort of guy, which, as an Oxford professor with more than 500 scientific articles and 10 books to his name, he clearly isn't. Typically, his favourite work is his contribution to Ladybird's Expert Books – an update of the classic children's series – on artificial intelligence. "I'm very proud of this," he says, as he hands me a copy from his bookshelf. We're in his study in the University of Oxford's somewhat municipal computing department on a sunny spring day.
Wooldridge is an adept public communicator, especially on artificial intelligence – a field he has worked in for more than 30 years, but about which he retains a healthy scepticism. In his 2023 Christmas lectures for the Royal Institution, titled The Truth about AI, he brought in a robotic dog and asked his school-age audience to vote on whether they'd whack it with a baseball bat. And, to explain reinforcement learning, he recreated the classic 80s movie WarGames, in which a young Matthew Broderick averts nuclear catastrophe by getting the US military computer to play noughts and crosses with itself.
WarGames is actually pretty close to the subject of Wooldridge's latest book, Life Lessons from Game Theory: The Art of Thinking Strategically in a Complex World. He's taught the subject to his students for more than 15 years, he says. Now it's our turn. There's no maths in Wooldridge's book; instead he translates game theory into 21 digestible scenarios, incorporating everything from Atlantic cod fishing, to Pepsi v Coca-Cola, to the existence of God.
"It is surprising how many global events can be explained by a relatively small number of game theoretic models," Wooldridge says. One of the simplest is the game of "chicken", which he illustrates using the James Dean movie Rebel Without a Cause. Two teenagers drive their cars towards a cliff; the first to jump is the "chicken", and loses the game. If both jump at the same time, it's a draw; don't jump at all and you've lost the game pretty badly.
The theory lesson here is about Nash equilibriums – but, practically, we see this game playing out in real life all the time. The Cuban missile crisis used to be the go-to example, but another one is unfolding as we speak: the US-Iran conflict. "You've got two sides with ever-escalating threats against each other; somebody's got to back down at some point," says Wooldridge. "The danger is, if neither backs down then you've passed a point of no return and you get the worst-case scenario for everybody."
Is there any way out? "Well, one of the ways that a game can get changed is if a third party comes in and provides some incentive for one of the parties to behave in a different way." Another option is to circumvent the game by communicating with your opponent. That's what happened in the Cuban missile crisis, but it feels less likely here. "Although, I have to say, Iran seems to be playing it a lot more cannily, in the sense that the US side is very, very unpredictable."
Wooldridge stresses that game theory is not just about warfare. He defines it as "a mathematical theory that aspires to understand situations in which self-interested parties interact with one another." That could apply to all manner of situations: social, political and philosophical.
The concept of the "zero-sum game", for example, has become a mainstream term, even if it's widely misunderstood. A zero-sum game is not simply one where one side gains what the other side loses; it is one where the incentive is to make your opponent lose as badly as possible. So, technically, chess is not a zero-sum game because you're just trying to win, not to destroy or humiliate your opponent. "This zero-sum mentality is very damaging. It's a very male trait," he says. "And the evidence is that, not only do you end up not necessarily doing as well in life as you could do, but actually you end as a more miserable person."
This adversarial worldview is the engine of populist politics – in the "migrants are coming to take your jobs" sense. One of Wooldridge's favourite games encourages us to think the opposite: the Veil of Ignorance was devised in 1971 by the philosopher John Rawls. The premise is that you can design society in any way you want, but afterwards, you will be placed randomly within it. Wooldridge describes it as "a beautiful thought experiment … It incentivises a socially desirable outcome, but people are still following their self-interest."
It's not initially clear how game theory fits with AI, but the former is a big part of the latter these days, Wooldridge explains, especially in his primary area of interest: multi-agent systems – programs that interact with one another and act on your behalf. "So if I want to arrange a meeting with you, why would I call you up? Why doesn't my Siri just talk directly to your Siri?" These types of interactions are embedded in our online life. "If my agent is going to interact with your agent and my preferences are not necessarily aligned with yours, then the theory that explains how you should think about those interactions is game theory."