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符号语言如何驱动了集体学习,以及它如何把人类与其他物种区分开来. Sal Khan 创建




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 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 are 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 someplace 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 of 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 kind of showing not showing and telling just showing and so because this is such a this is such a a unprecedented they're really all the nuances of what this chimpanzee might be able to 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 specific movements or what you or what you might be able to kind of 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 there may be able to learn of the same amount again able to learn maybe the same amount again but then when they need to communicate it they have the exact same problem they have it's hard to communicate it with their with what they have in 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 type of circumstance is generation after generation even though there is learning over the course of an individual chimpanzees life and even though they can communicate to some of that to each other that form of communication is so it 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 symbolic language and I'll talk about this in a second but it's 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 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 it's a very precise a 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 the next to some other human being maybe it is the offspring maybe it is another member of the tribe or the group 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 their own nuances and their own innovations and this one right over here might come up with his or her own 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 tie of years went when it's good to do it 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 so strong precise precise efficient communication efficient communication communication you what you have is a human group or eventually a human civilization is a label able to have a collective memory is able to have a collective memory in the case of the chimpanzees there every generation every champions 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 what this might be passed on so all of this might be passed on or a good chunk of this could be passed on to the next generation and I'm not even talking about written language yet this could even 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 this 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 and maybe this is one of the reasons why humans even have larger memories because there is all of this collective knowledge to gain from 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 in to 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 so let's say you copy let's say you paste that this other human being that's maybe living at the same time and when that becomes relevant 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 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 specific domains and adapt specific 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 as an example of that there's 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 are 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 gymnast a you know a lawyer understands philosophy speaks twenty 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 don't don't some you know for example even monkeys when they screech when they're when there is in 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 could convey certain things maybe it's when they are maybe it was 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 and 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 it's a warning but there's no deep nuance or deep precision that's being able to convey by these 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 it is a symbolic language and when I say it's a symbolic language I'm even saying it in a broader sense than even just written symbols I'm talking about even the sounds themselves as so let's 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 one and it has some meaning let's call it meaning one meaning one so this might be a certain type of scream it means that a Predator is approaching then you might have something like a sound - or gesture - and then it has some other meaning it has meaning - it might be a certain type of song which means that I am in the mood to reproduce or whatever else you might have gesture three gesture three that has some direct meaning it might mean that I have found food or something like that so meaning three what humans have they can do this where particular sounds have particular meanings so for example in humans you could have sound one it refers to meaning one I'll just refer to meaning one you could have sound two that refers to meaning two you could have sound 3 that is 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 meetings so what 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 one sound to sound three will now have another meaning meaning four then you can maybe have a combination where you have sound three sound one and sound two might have meaning five and if you have tens of thousands of sounds when 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 one is the sound me saying the word dog and I'm not even gonna write it down because I want to imagine a world even before written communication so sound one is the sound dog sound two is a sound eats and sound three is the sound man so literally sound one if you've heard dog you think okay I visualize a dog of some type and even there that you know you know well you'd have some visualization of a dog and we all have one maybe sound two if you heard eats you'd say okay I imagine eating in some way and sound three man you have some visualization on 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 a much more complex meaning than just referring to certain objects or certain actions or you could have man eat dog and it's not pleasant but I guess in a desperate situation but once again it is another meaning that 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 prop 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 from one entity to another