One of the most important bits of game, or so a lot of people think, is decision-making. But then people point out the fact that some of the social games don't actually require much decision-making. It's actually more of a task list.

PM: I think decision-making is of paramount importance in certain games, yeah. And you can boil down a person's activity into decision-making if you particularly want to. Is there a lot of decision making in the Half-Life series? It's a corridor-based game. There's one way through. Well, you could say you do decide...

Tactical decisions.

PM: Yeah, maybe tactical decisions, but then I think you're trying to take what is a simple word like "decision-making" and trying to fit it into lots of different buckets. Is there decision-making in The Sims? Yeah, but it's much more complex decision-making. Or an RTS? Much more complex. So it's a very simple term, which you're trying to fit into lots of these other terms.

I found it very interesting that you said the idea of simply making a game and putting it out is over -- as you put it, "the idea of handing down an idea is over." Essentially I think what you're referencing is working on a console game for two years, and then putting it out in a box is over.

PM: And you go on holiday.

Do you really believe that it's over?

PM: I do. It's over. It's over. It's unthinkable to me experiences -- that it's so easy to get feedback and continue to refine -- that we wouldn't do that. Why would we not continue to change and tweak it? Now, I'm sure there will be exceptions, but if you have the ability to look at what people are enjoying and what they're getting stuck on, and the ability to change that, why wouldn't you change it? Of course you would.

With Curiosity, there's this degree of players collaborating, but sort of competing too. There's this push and pull. That really interests me, that way of looking at multiplayer. Can you talk a bit about that?

PM: The multiplayer encompasses the whole world. When we're all -- I couldn't show on stage because we didn't have enough people on the cube at the moment -- when you actually see thousands of people play, it's an amazing experience, because people collaborate. They do things together. They get the idea.

At the moment, in the cube, you can't text. All your ideas have to express through the space, which is quite interesting. And of course, people will collaborate, but ultimately it comes to, there's going to come a point when the cube gets small enough where people start realizing, "Shit, there's not long to go. I don't know if I want to collaborate anymore because only one person is going to find out what's in the middle." And the number of taps required on the last surface will be the number of active users, so everyone will get one tap, and that's going to be frantic.

Wow.

PM: And this will be so interesting, to see what people do. They may just give up, or they may just tap obsessively, or they may just want to find out what's below each surface.

Or 4Chan might try to organize and grief it.

PM: Cheating is a real problem for us. We were worried about cheating, because someone could write a bot -- someone actually said they're going to have one of those dipping birds, and just put them in front of the key, and have it just dip away. [laughs] It's not really feasible, because it would have to dip and scroll.

Someone could do something with scripting, though, potentially.

PM: It's difficult. It's difficult. We have had to think about that, and obsess about that a bit, because it could be that we just put it live and then 24 hours later, see this cube just shrink down in front of our eyes.

Well also there's the idea that things are going to emerge once the game goes live that you're not anticipating.

PM: That's why it's called an "experiment", because we can't pre-think this stuff.

And do you think that that's going to influence the direction you take with the different layers?

PM: Yeah, for sure. The different layers, and the final game that we're making. There's enough layers that we can adapt the experience. My prediction is that it will last for quite a few months, and that means we have time to adapt the experience accordingly.

You talked about the idea that you're working on a big game -- a quote-unquote "big game." I don't know what that means, and it probably doesn't mean what it used to mean to you.

PM: It's big in its ambition. It's huge in its simplicity. And it's on a massive scale. Not on a massive scale as in you know, it's a triple-A game that takes 20 to 60 million to make, but it's on a massive scale because it's an idea for the world. In the way a bit like the cube is an idea for the world. But the cube isn't a game, as such. Well, that's why it's called an experiment. It's an experience.

Do you think that maybe ambitious ideas are now more important than big experiences?

PM: This is going to sound a bit philosophical. Maybe I'm just a bit tired, and I get a bit emotional when I'm tired. But whenever mankind is faced with these huge challenges, it always comes up with big ideas that change the world. Whether that's the industrial revolution, or the spinning jenny or whatever it is, or how you use steam, or how you use electricity.

But I think that these things now [taps iPad] are great pieces of hardware. There just aren't great pieces of software to match those pieces of hardware, and history proves that a vacuum is always filled. Something will fill that which really amazes us. There's nothing that defines this, in the same way that consoles were defined by certain gaming experiences. So I think there's just loads of space for innovation.