The news that a computer program has beaten Go master Lee Se-dol in a best-of-five competition may have shocked some readers. In this post, I’d like to explain why I don’t think it matters much at all, by telling a little story about three guys named Tom, Sam and Al.
Tom has a brilliant mind. He puts his perspicacious intellect to good use by playing mentally challenging games, and he always wins. Tom’s freakish ability to win games by performing astonishing leaps of mental intuition leaves many spectators baffled. “How on earth do you do it?” they ask him, whenever he chalks up a victory against yet another hapless opponent. “It’s a strange gift I have,” Tom answers modestly. “I can’t really explain it, even to myself. I just have these mysterious intuitions that come to me out of the blue, and that enable me to win.”
Tom’s reputation spreads far and wide. Those who witness his spectacular triumphs are amazed and dumbfounded. After a while, people start calling him the world’s best game player.
How Sam beat Tom
One day, a stranger shows up in town, named Sam. Sam walks up to Tom (who is sitting in a bar) and says to him in a loud voice, “I can beat you!”
“No, you can’t,” answers Tom, “but you’re welcome to try anyway. Name your game.”
“Chess,” says Sam. “You know what they say: it’s the game of kings.”
“Good choice,” replies Tom. “I love that game.”
“I have a question,” says Sam. “Do you mind if I get some assistants to help me choose my moves?” “Not at all,” answers Tom. “I’m quite willing to be generous. Bring as many assistants as you like.”
Sam has one more question. “Since I have a very large number of assistants, do you mind if I contact them via email while I play, instead of bringing them all here?”
“Not at all,” replies Tom. “That’s fine by me.”
“That’s a big relief,” says Sam. “Actually, I have millions and millions of assistants. And it’s a good thing that they’re helping me, because I really don’t know much about chess. Nor do they, for that matter. But together, we’ll beat you.”
Now Tom looks puzzled. “How are you going to beat me,” he asks, “if you don’t really know the game?”
“By brute force,” answers Sam. “Each of my assistants is good at just one thing: evaluating a chess position. Thanks to my army of assistants, who are extremely well-organized and who are also very good at rapidly evaluating positions and sharing information with one another via email, I am effectively capable of evaluating hundreds of millions of chess positions in just a few seconds. I’ve also compiled a list of good opening and closing moves, as well as good moves in various tricky situations, by studying some past games played by chess experts.”
“Well, that sounds like an interesting way to play,” says Tom. “But speed and a list of good moves are no substitute for intuition. You and your assistants lack the ability to see the big picture. You can’t put it all together in your head, like I can.”
“We may lack your intuition,” responds Sam, “but because we’re fast, we can evaluate many moves that would never occur to you, and what’s more, we can see further ahead than you can. Do you want to try your luck against us?”
“Game on!” says Tom.
After just 20 minutes, it’s game over for Tom. For the first time in his life, he has been soundly defeated. He and Sam shake hands in a gentlemanly fashion after the game, and return to Tom’s favorite bar, where they both order a beer.
Tom is quiet for a while. Suddenly, he muses aloud, “I think I finally understand, Sam. What you’ve taught me is that the game of chess is fundamentally no different from a game of noughts and crosses, or Tic-Tac-Toe. It’s a game which yields to brute force calculations. My intuition enables me to see ahead, and identify lots of good moves that my opponents can’t see, because they’re not as far-sighted as I am. But your brute-strength approach is more than a match for my intuition. I’m limited by the fact that I can’t see all of the good moves I could make. You and your army of assistants can do that. No wonder you won, when you played me. Still, it’s taught me a valuable lesson about the limits of human intuition. Congratulations on your victory.”
“So you’re going to give up calling yourself the world’s best game player?” asks Sam.
“Not quite,” answers Tom. “From now on, I’m going to call myself the world’s best player of interesting games. By an ‘interesting game,’ I mean one that doesn’t yield to brute-strength calculations – in other words, one that requires a certain degree of intuition in order to be played well.”
“Would you care to nominate a game that fits that description?” inquires Sam.
“My nomination is the game of Go, which has been called the most complex of games,” replies Tom. “The number of possible positions on a 19 x 19 Go board is 10170, which is far greater than the number of atoms in the universe. “There’s no way that you and your army of assistants can evaluate that many moves. Admit it: you don’t have a hope of beating me at Go.”
“You’re right; we don’t,” acknowledges Sam. “But I know another man who I think can beat you. His name is Al. Remember that name. At the moment, he’s perfecting his game, but he’s improving by leaps and bounds. You’ll probably see him a few years from now.”
“I look forward to the challenge,” replies Tom. “Farewell, Sam, and take care.”
Al arrives in town
A few years later, Sam’s prophecy comes to pass. A peculiar-looking man in a dazzling purple cloak rides into town, and asks to see Tom. “Hi, Tom. I’m Al,” he says. “I’d like to challenge you to a game of Go. Although I have none of your brilliant intuition, I’m quite confident that I can win.”
“I really don’t see how you can,” answers Tom. “Even if you had an entire universe full of people helping you to choose your next move, there’s no way you could possibly see far enough ahead to properly evaluate all possible moves you could make. Without a brute strength approach, you really need intuition, in order to win.”
“Oh no you don’t,” Al replies. “It turns out that the game of Go has a long, long history which you know nothing about. On Earth, it first appeared in China, more than 2,500 years ago. But it was brought to Earth by aliens. I’ve been in contact with them: in fact, it was they who gave me this colorful cloak, which can instantly turn any color I tell it to, as well as turning invisible.”
“Wait a minute,” interrupts Tom. “Forget about the cloak. You mean to say I’ll be playing against a bunch of aliens?”
“By no means,” replies Al. “You’ll be playing against me, and I can promise you, I won’t be talking to any aliens, either. But I should tell you that aliens have been playing the game of Go for billions of years: in fact, there’s even an inter-galactic Go club. However, they play it in a very different way from you, Tom. They don’t rely on intuition at all.”
“How do they play, then?” asks Tom, perplexed.
“They play incrementally, by gradually building up a set of smart and successful moves in various situations,” answers Al. “A long time ago, the list of smart moves was fairly short: you could fit them all in one book. Now, after billions of years, the list is much bigger. When aliens play Go, they do so by following the rule book up to a certain point, and then trying out something a little bit new and different. It doesn’t make for very exciting games, but it does make for smart tactics. Recently, the aliens were kind enough to give me their list of moves. However, it’s so big that I’ll require an army of earthly assistants to help me search through the list, in order to keep within the time limits of the game. None of these assistants knows anything about the game of Go, but they’ll be communicating with me via email. I have to say that I know very little about the game of Go myself, but I’m going to be playing by the aliens’ rules. Is that all right with you?”
“Certainly,” replies Tom. “The aliens’ way of playing sounds rather dull to me. I’m going to spice up the game with some human intuition. You’ll soon see that nothing can beat intuition, in an interesting game like Go, where the best move can’t possibly be calculated.”
They sit down to play. After about an hour, Tom is forced to resign. In a dazed tone of voice, he asks, “How did you do it, Al?”
“I think I can explain, although I’m no Go expert,” answers Al. “Essentially, what I did was to pool the combined wisdom of billions of players who came before me. You were playing against that. What my victory means is that a sufficient amount of experience can beat human intuition, in a tactical game. But that’s hardly surprising, is it?”
Tom reflects for a while and finally replies, “No, Al, it isn’t. I was wrong to think that I could defeat the combined wisdom of so many players. I’ve come to appreciate the limits of human intuition. What I’m wondering now is: are there any situations where intuitions are indispensable?”
Tom reflects on the nature of human intuition, and where it might prove indispensable
Tom ponders again for a while. After a long silence, he announces, “I think I can see two kinds of cases where intuitions are indeed irreplaceable. One is in a game where the goal cannot be described in objective, “third-person” language; it can only be described in subjective terms which refer to the beliefs, desires and intentions of the other players. To win the same, you have to be able to put yourself in other people’s shoes. While a list of ‘smart moves’ might serve you well up to a point, it won’t help you in novel or unexpected situations, where you can only figure out what you should do by asking yourself what the other person would want you to do in that situation. Experience can never trump empathy.”
Tom continues: “The other case I can think of where intuition would be needed is in a situation where trying out incremental improvements won’t help you to get from A to B, simply because there are too many improvements to try out, making the search for the best move like searching for a needle in a haystack. Experience won’t help here, because there isn’t enough time to narrow down the search. Without a flash of insight, you’ll never be able to spot the right move to make, in moving towards your desired goal.”
Al is curious. “Would you care to offer any examples of these two cases you’ve proposed?” he asks.
“Happy to oblige,” answers Tom. “Right now, in the United States, there’s a presidential election going on. Politics is a game, and the U.S. presidential election is a winner-take-all game. But it’s not enough for the successful candidate to be a policy wonk, who knows how to fix the American economy, or even a ‘steady pair of hands,’ capable of handling any domestic or international crisis that might come up. You need more than intelligence and experience to win a presidential election. You need to be a good speaker, who is capable of inspiring people. You also need to be capable of leadership, so it definitely helps if you have a commanding presence and ‘sound presidential.’ It helps, too, if you have excellent networking skills, to help you raise lots of money, which you’ll need to finance your campaign. In addition to that, you need to be a fairly likable person: nobody wants to elect a curmudgeon, no matter how clever, experienced or commanding he or she may be. On top of that, you need to be capable of empathy: you need to be able to show the public that you are genuinely capable of feeling other people’s pain, or people will spot you for a phony and dismiss you as cold and uncaring. Oh – and you’d better at least as ethical as your opponents, or people will perceive you as a liar and a crook, and they probably won’t vote for you. As you can see, many of these skills require the ability to identify with other people. You simply can’t bluff your way through a presidential campaign with a catalogue of smart moves or canned responses. It’s too unpredictable. Let me put it another way. You could design a robot that could beat a human at the tactical games I’ve practiced playing, over the years. But you could never design a robot that could win an American presidential election. Only a human being who is capable of genuine empathy and of intuiting the right thing to do when interacting with other people could win a contest like that.”
“Interesting,” says Al. “What about your other case?”
“Protein design would be an excellent example of a challenge requiring leaps of human intuition,” answers Tom. “Very short proteins might arise naturally, but once you get to proteins that are more than 150 amino acids in length, the space of possibilities is simply too vast to explore, as Dr. Douglas Axe demonstrates in his 2010 paper, The Case Against a Darwinian Origin of Protein Folds. In his own words:
The difficulty stems from the fact that new protein functions, when analyzed at the level of new beneficial phenotypes, typically require multiple new protein folds, which in turn require long stretches of new protein sequence. Two conceivable ways for this not to pose an insurmountable barrier to Darwinian searches exist. One is that protein function might generally be largely indifferent to protein sequence. The other is that relatively simple manipulations of existing genes, such as shuffling of genetic modules, might be able to produce the necessary new folds. I argue that these ideas now stand at odds both with known principles of protein structure and with direct experimental evidence. If this is correct, the sampling problem is here to stay, and we should be looking well outside the Darwinian framework for an adequate explanation of fold origins.
“I’d say a situation like that calls for the intuitive insight of an intelligent designer, wouldn’t you?” asks Tom.
“If Dr. Axe’s premises are correct, then it’s difficult to avoid that conclusion,” concedes Al. “But I’m not a biochemist, so I can’t really say. Still, I can at least see what you mean, now. One thing troubles me, though.”
“What’s that?” asks Tom.
“The two kinds of cases you’ve described are quite different in character,” replies Al. “One requires the ability to put yourself in other people’s shoes, while the other requires the ability to make a mental leap that surpasses the power of any computer or any trial-and-error process. What I’d like to know is: what is it that ties these two kinds of cases together?”
“That’s a very good question,” answers Tom. “I really don’t know. What I do know, however, is that all my life, the games I’ve been playing are only a tiny subset of the vast range of games that people play in real life, let alone the truly enormous set of games played by the Creator of the cosmos, when designing Nature. I’ve now come to realize that losing at chess and Go doesn’t matter very much, in the scheme of things. There are far more interesting games to play. And now, I’m off.”
“Where are you off to?” asks Al.
“Washington,” answers Tom. “I’m going to try my hand at political forecasting. Maybe I’ll succeed, or maybe fall flat on my face. But you’ve given me a lot to think about, Al. I’m going to try out some of the new ideas you’ve given me, and put them to the test. Wish me luck!”
I shall end my story there. I wonder if any of my readers can shed some light on the question posed by Al on human intuition, at the end of my story. What, if anything, unifies the two kinds of cases I have described?
Before I finish, I’d like to quote a short passage from an article by philosopher David Oderberg, who is now professor of philosophy at the University of Reading, England. In an article in the Australian magazine Quadrant (Vol. 42, No. 3, 1998: 5-10), he wrote:
“…[T]he game of chess, in itself, is nothing more than glorified noughts and crosses. Sure, it can be played with finesse, ingenuity, artistry and so on; but that is peripheral. In essence, chess is a formal system of well- defined axioms and rules, with a well-defined goal. No wonder a computer can play it at all. We should be amazed if it couldn’t.”
Food for thought. And now, over to you.
P.S. Perceptive readers will have noticed some similarities between my story and philosopher John Searle’s Chinese room thought experiment. My intention here, however, is not to address the question of whether computers think, or whether they are conscious, but rather, to explore the strengths and weaknesses of human intuition.