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Current time:0:00Total duration:13:17

Video transcript

There are many things that differentiate human beings from other species. But the one thing that probably differentiates humans even from our closest relatives in the animal kingdom in a really big way is the notion that humans are collective learners. And to understand that, let's think about how even our closest relative in the animal kingdom, the chimpanzee, might communicate. So you might have one chimpanzee, and over the course of his or her lifetime, they're able to learn a bunch of cool experiences. And they're even able to learn to use tools, manipulate tools, and-- who knows-- maybe even make tools. Maybe even get a twig some place and take off the leaves and then use that to go get ants out of a hole or whatever else. So they're able to learn all this stuff over a lifetime. Now unfortunate for chimpanzees-- well, what is fortunate for chimpanzees is they do teach some of these things that they've learned to other members of their group, often their offspring. But what's unfortunate for chimpanzees is they don't have a great way to communicate with each other. So for most chimpanzees, the way that they're able to teach is essentially by showing-- not showing and telling, just showing. And so because this is such a un-precise or not exact and such an inefficient way of communication, really all of the nuances of what this chimpanzee might be able accumulate over his or her lifetime aren't able to be conveyed to the next generation or to the other chimpanzees around. So you have tremendous energy loss. And in particular, all that can be conveyed are maybe the to specific movements or what you might be able to observe in the present. All of the other things that maybe the chimpanzee is learning about-- the times of year where this is appropriate, and maybe they can convey some of that by showing them at the right times of year-- but other nuanced aspects of it, or particular ways to hold something, or twist something, can only be shown. It can't be described in a very precise way. So you have all of this loss of experience, this loss of information. And then over the course of these animals' life, they may be able to learn the same amount again. But then when they need to communicate it, they have the exact same problem. It's hard to communicate with what they have at their disposal, which is really just showing the other chimpanzees what they've done. And so once again, you have a loss of information. And what you have in this type of circumstance is, generation after generation, even though there is learning over the course of an individual chimpanzee's life, and even though they can communicate some of that to each other, that form of communication loses so much information and so much nuance that you never have an overall accumulation of knowledge and wisdom in this chimpanzee population. Now humans, on the other hand, have something called a symbolic language. And I'll talk about this in a second. But for now, it's safe to say that human language is far more precise and far more efficient than just being able to show someone something. Imagine if you had to learn how to do something without being able to communicate verbally, if you just had to look at someone else's actions. And then you'd have a good idea of how difficult it is for chimpanzees to teach each other. But in the case of human beings, we have this thing called symbolic language. That's a very precise, very efficient way of communicating. So from one human being to another, you can actually communicate a good deal. Maybe not every single nuance and every single experience, but a good chunk of it. So right here, I'm drawing about that much of it to some other human being. Maybe it is the offspring. Maybe it is another member of the tribe or the group or whatever it is. And then this human being might come up with some other innovations. They're able to build off of all of this learning from that previous generation or from that other human being that's around. And they're able to come up with their own nuances and their own innovations. And this one right over here might come up with his or her own the nuances and innovations. And because they have a good communication mechanism, this one could even communicate to that one what he's learned or what she's learned and communicate a good chunk of that. Maybe not all of it, but maybe a reasonable bit. They can describe exactly how they do something, the times of years, when it's good to do it, and when it's not good to do it, how to plan for the future, what's the history of this new learning. And so what you have going on here is because of this strong communication mechanism, precise, efficient communication, what you have is a human group, or eventually a human civilization, is able to have a collective memory. In the case of the chimpanzees, they're every generation. Every chimpanzee is having to relearn the things that the other chimpanzees might have already done in previous generations. They're not able to really move forward or build on those in significant ways. In humans, as information is learned and experience gained, a good bit of that is able to be passed on to other humans. And so this might be passed on. So all of this might be passed on or good chunk of this could be passed on to the next generation. And I'm not even talking about written language yet. This could still just be oral communication, which is still a very strong, precise, efficient means of communication. Written communication takes it to another level. But then this person over here, maybe she comes up with other innovations. And at some point, you might say, well, look if everyone keeps having innovations and they keep learning what everyone learned in previous generations, maybe this will tap out the total amount of memory that a human being even has. And there's actually a case that maybe this is one of the reasons why humans even have larger memories, because there is all of this collective knowledge to gain from one generation to another, from one human being to another. But there are some limits to this. And this is the other element where this collective aspect of collective memory and collective learning becomes really powerful. A human being, because of the strong communication mechanism, is not just limited to the knowledge and the experience in their memory. They are able to tap into-- So this human being right over here does not have this skill set. And that skill set maybe gets passed on to another human being. So let me copy and paste that. This other human being that's maybe living at the same time. And when that becomes relevant, they could actually tap into it. And maybe they could learn it from that human being. Or maybe it's in a different part of society and this human being can build certain tools or build certain things using this information, using that knowledge right over there. And then this human being doesn't need to know that information. They can just leverage the output of that information to then build on top of it. So what it allows human beings to do is not only convey information, and build on information, from generation to generation, human to human, it allows all of the human brains collectively at any given point of time to be one collective memory bank that can be used to develop or innovate and for specific domains and adapt to specific parts of the ecosystem or to teach each other. So all of a sudden, this is really unique, as far as we can tell, in the animal kingdom. All of a sudden, it's not all about the brain or the memory of one individual member of a species. It now becomes about the brain or the memory of the entire civilization or the entire group of the species. And just an example of that, as far as I know, there's no human being who knows how to do everything that all human beings know how to do. I could imagine that there is a chimpanzee that knows how to do everything that any other chimpanzee knows how to do. There are no humans that can be a fighter pilot, a doctor, a gymnast, a lawyer, understands philosophy, and speaks 20 different languages. As far as I know, that human being does not exist. And that's OK, because they can tap into the experiences, the abilities of other human beings to build up their civilization. None of us, as far as we know, knows how to do everything that we need to actually build our civilization. But the information is in our collective memory to actually do it. Now the next thing you might say is, OK, I started with this premise that we have a strong, precise, efficient means of communication, and that other animals don't. But don't other animals actually have some form of language? So for example, even monkeys. Wouldn't they screech when they are in danger? That's a form of communication, maybe a form of language. Maybe certain animals-- birds, monkeys-- maybe they have a song that they sing that can convey certain things. Maybe it's when they are looking for a mate. Isn't that a form of communication? And these are. These are a form of communication and a form of language. But these don't really come in play in terms of the teaching/learning. You don't see one chimpanzee making screeching sounds or learning sounds. They might do a little bit, just to warn, maybe as a warning. But there's no deep nuance or deep precision that's being able to convey by these one-off sounds or even one-off gestures. And what's particularly powerful about human language is that it is a symbolic language. And when I say it's a symbolic language, I'm even saying it in a broader sense that even just written symbols. I'm talking about even though the sounds themselves. So let's go to a time where we did not even have writings. And when we talk about symbolic languages, let's think about a non-symbolic language. So in a non-symbolic language, you might have some sound. Let's call it Sound 1. And it has some meaning. Let's call it Meaning 1. So this might be a certain type of scream. It means that a predator is approaching. Then you might have something like a Sound 2 or Gesture 2. And then it has some other meaning. It has Meaning 2. It might be a certain type of song, which means that I'm in the mood to reproduce or whatever else. You might have Gesture 3 that has some direct meaning. It might mean that I have found food or something like that. So Meaning 3. What humans have, they can do this, where particular sounds have particular meanings. So for example, in humans, you could have Sound 1. It refers to Meaning 1. I'll just refer to it as Meaning 1. You could have Sound 2 that refers to Meaning 2. You could have Sound 3 that refers to Meaning 3. So these are just direct representations. But what is really powerful about symbolic languages, is that these oral symbols can be combined according to set rules or grammars to have an infinite number of meanings. So this is what really makes human language transcend other languages and really makes it this robust, precise communication mechanism, is you could have combinations. Sound 1, Sound 2, Sound 3 will now have another meaning, Meaning 4. Then you could maybe have a combination we have Sound 3, Sound 1, and Sound 2 might have Meaning 5. And if you have tens of thousands of sounds, and really our oral words are those sounds in a given language, then all of a sudden, you can have infinite meanings by putting them in different combinations. And if you think this is a little bit abstract imagine that Sound 1 is the sound of me saying the word "dog." And I'm not even going to write it down because I want to imagine a world even before written communication. So Sound 1 is the sound "dog." Sound 2 is a sound, "eats." And Sound 3 is the sound "man." So literally, Sound 1, if you heard, "dog," you'd think, OK, I'd visualize a dog of some type. And even there, you'd have some visualization of a dog. And we all have one maybe. Sound 2, if you heard "eats," you'd say, OK, I'd imagine eating in some way. And Sound 3, "man," you have some visualization of it. And if it was a non-symbolic language, that's all you could get out of those three sounds. But now, in a symbolic language, we can combine those. We could say, "dog eats man." So once again, we just reused the three sounds, the three symbols. But now, they're referring to a whole new, much more complex, meaning than just referring to certain objects or certain actions. Or you could have, "man eats dog." It's not pleasant, but I guess in a desperate situation. But once again, it is another meaning that we can get out of the same sounds. And what these symbolic languages do, besides giving you an infinite number of meanings, they're allowed to give you more nuance, and really refer to things that are abstract, and including-- and maybe most importantly-- things like the present, the future, the past, kind of hypothetical things that really are necessary in order to really communicate or optimally communicate all of the experiences or the learnings from one entity to another.