Here's an example. This is a video that really illustrates what we're gonna talk about in terms of theory of mind, which is the mechanism that people think is really special about humans. Or at least there's something special about it in humans. And this video is a really fun illustration. And what I want you to do is just ask yourself, are these shapes or are these beings moving in the video? So what you can't help but see as a human is that those two shapes have a relationship. And that the red triangle is trying to help the timid blue triangle exit the small box and interact together with it outside in the larger space. You attribute goals, you attribute emotion when they spin and they're happy. And you can't help but as a human see those things in shapes, two-dimensional shapes, that clearly do not have any of those psychological attributes. So that is the big thing that people have focused on about human social cognition that people think might be really special about our species. Is that when we develop and as we interact as adults and we solve all types of problems, we are constantly relying on the ability to think about the thoughts of others. We are aware that others have perceptions, that they see or hear things. They have intentions like goals and desires, that they have emotions, that they feel things and that obviously other people have knowledge. But what becomes even more complicated is that we know, and as you develop you develop an understanding that different individuals can have perceptions and intentions and emotions and knowledge that can be different from your own. You can have people that have intentions that are completely different from yours, emotions that are the same. And in each interaction we're constantly trying to assess not only what our mental states are, what our perceptions, intentions, emotions and knowledge are, but what the other person or the other people we're interacting with, what they are experiencing mentally. We can actually think about the thoughts of others. So one of the things that's really interesting, though, is while this is such an important ability for our species, we really use what are quite simple cues, or clues to try to think about what the thoughts of others are. And one of the really powerful ways you can determine what somebody else is thinking, and you do it all the time, and you can't help it, is you use social cues. So for instance, you see somebody looking in one direction, and you might then think to yourself, well, that's funny. Why is that person looking in that direction? He must see something, or she must see something, that I don't know about. So if I was all of a sudden to look up and stare at the ceiling, even though you know that I am giving that as an example, you still are a little bit surprised and you're thinking about why I would do that. And in this case I don't see anything, but I'm actually trying to help you understand the point I'm trying to make. So that is theory of mind in action. It ends up that when people have looked at this in animals, animals also use social cues. This is an example of an experiment I did with a chimpanzee, very simple. I look up and Doreen the chimpanzee also looks up. And so one of the things that people have asked is, is it that humans are the only species that are able to think about the thoughts of others and think about perceptions, intentions, emotion and knowledge in others? Or is it that lots of other species can think about the thoughts of others? And of course, there's been a lot of interest in our close relatives, the bonobo and chimpanzee, as to whether they can think about the thoughts of others. Now, just to give you another concrete example of how you use social cues, when you are at a party, or you go to a class reunion, and you see lots of people that you've known before. And you're talking to your good friend, and there's Bob and you've know Bob for years and you're so excited to see them. And while you're talking you see Bob just very subtly look down with his eyes, not moving his head, just moving his eyes down and look at your name tag. You immediately know just from Bob moving his eyes that Bob doesn't know who you are. That's another great example of how we use subtle social cues to get inside the minds of others and understand what they're thinking about the thoughts of others. It's a very important ability that we use in all sorts of different contexts. And while we've seen, for instance, Doreen in this video using social cues, there's been the larger question of how sophisticated are animals in thinking about the thoughts of others? Or is it when Doreen looks up when I look up, she's doing something completely different? She's just learned that when somebody looks up there's something interesting there and it's not that she's thinking about the thoughts of others at all, and that thinking about the thoughts of others, or theory of mind is really a human trait.