Ron Eglash: The fractals at the heart of African designs

131,861 views ・ 2007-12-07

TED


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翻译人员: Jiayi Li 校对人员: Weihua ZHANG
00:13
I want to start my story in Germany, in 1877,
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我的故事发生在1877年,
00:16
with a mathematician named Georg Cantor.
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当时有位德国数学家叫乔治·康托(Georg Cantor)。
00:18
And Cantor decided he was going to take a line and erase the middle third of the line,
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有一天,他做了这样一件事:把一条线段分成三份,擦掉中间一份,
00:23
and then take those two resulting lines and bring them back into the same process, a recursive process.
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然后对剩下的两条线段进行同样的操作,周而复始。
00:28
So he starts out with one line, and then two,
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于是他从一条线段得到两条,
00:30
and then four, and then 16, and so on.
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然后是四条,然后十六条,不断增加。
00:33
And if he does this an infinite number of times, which you can do in mathematics,
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如果他这样重复操作无限次 (在数学中你可以做到),
00:36
he ends up with an infinite number of lines,
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最终他就会得到无数条线,
00:38
each of which has an infinite number of points in it.
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而每条线又由无数个点组成。
00:41
So he realized he had a set whose number of elements was larger than infinity.
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于是他意识到,他拥有一个集合——这个集合的元素个数比无穷还要多。
00:45
And this blew his mind. Literally. He checked into a sanitarium. (Laughter)
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这简直让他发疯了。我没有夸张,他为此进了疗养院。
00:48
And when he came out of the sanitarium,
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当他从疗养院出来以后,
00:50
he was convinced that he had been put on earth to found transfinite set theory
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他坚信自己是被上帝派来寻找超限集合论的,
00:56
because the largest set of infinity would be God Himself.
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因为最大的无限集便是上帝本身。
00:59
He was a very religious man.
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他是一个虔诚的教徒,
01:00
He was a mathematician on a mission.
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并把成为一名数学家当做自己的使命。
01:02
And other mathematicians did the same sort of thing.
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其他数学家也做过类似的事。
01:04
A Swedish mathematician, von Koch,
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例如,一位名为von Koch的瑞典数学家
01:06
decided that instead of subtracting lines, he would add them.
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有一天决定把线段相加,而不是想减。
01:10
And so he came up with this beautiful curve.
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最终,他得到了这样一段美丽的曲线。
01:12
And there's no particular reason why we have to start with this seed shape;
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其实我们选择这个图形作为起始形状没有什么特殊原因;
01:15
we can use any seed shape we like.
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我们可以选择任何图形作为起始。
01:19
And I'll rearrange this and I'll stick this somewhere -- down there, OK --
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让我把这把这个图形变一下,把这个放在--这下面,好--
01:23
and now upon iteration, that seed shape sort of unfolds into a very different looking structure.
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现在经过反复的操作,这个形状就被延展成了一种看似不同的形状。
01:30
So these all have the property of self-similarity:
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但这些图形都有自我相似的特点:
01:32
the part looks like the whole.
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每一小部分都跟整体相似。
01:34
It's the same pattern at many different scales.
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也可以说是同样的形状,只是大小不同。
01:37
Now, mathematicians thought this was very strange
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数学家们觉得这个非常奇怪,
01:39
because as you shrink a ruler down, you measure a longer and longer length.
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因为(勾勒图形的边缘)长度越来越长,而你的尺子看似越来越短。
01:44
And since they went through the iterations an infinite number of times,
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这些图形经过无数次重复的变化,
01:46
as the ruler shrinks down to infinity, the length goes to infinity.
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它们的长度趋向于无穷大,而相比之下,原先用于衡量他们边缘长度的尺子则趋向于无穷小了。
01:52
This made no sense at all,
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这一点道理也没有,
01:53
so they consigned these curves to the back of the math books.
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于是数学家们把这些曲线塞到数学书的背后,
01:56
They said these are pathological curves, and we don't have to discuss them.
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然后说这些是不正常的曲线,我们不用讨论它们。
02:00
(Laughter)
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(笑声)
02:01
And that worked for a hundred years.
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就这样,一百年过去了,
02:04
And then in 1977, Benoit Mandelbrot, a French mathematician,
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直到1977年,一位名为Benoit Mandelbrot的法国数学家
02:09
realized that if you do computer graphics and used these shapes he called fractals,
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意识到如果人们通过计算机来生成这些他叫做“分形”的图形,
02:14
you get the shapes of nature.
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便可以得到大自然的形状。
02:16
You get the human lungs, you get acacia trees, you get ferns,
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人们可以得到肺,洋槐树,蕨类植物……
02:20
you get these beautiful natural forms.
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各种美丽自然的形状。
02:22
If you take your thumb and your index finger and look right where they meet --
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如果你们看一看你们的拇指与与食指之间的部分--
02:26
go ahead and do that now --
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现在就可以看一下--
02:28
-- and relax your hand, you'll see a crinkle,
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把手放松,你们可以看到一段皱纹,
02:31
and then a wrinkle within the crinkle, and a crinkle within the wrinkle. Right?
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然后这皱纹扩展成更多的皱纹,然后更多,是吧?
02:34
Your body is covered with fractals.
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你们全身都被“分形”包围着。
02:36
The mathematicians who were saying these were pathologically useless shapes?
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那些认为“分形”不正常的数学家们,
02:39
They were breathing those words with fractal lungs.
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他们用分形的肺部呼吸,却说着那样的话,
02:41
It's very ironic. And I'll show you a little natural recursion here.
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多讽刺!现在我给大家演示一段自然的循环过程。
02:45
Again, we just take these lines and recursively replace them with the whole shape.
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跟之前一样,我们用几条线,然后重复用整体代替它们。
02:50
So here's the second iteration, and the third, fourth and so on.
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这是第二次循环,第三次,第四次……不断重复。
02:55
So nature has this self-similar structure.
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可以看到,大自然也有这种自我相似性。
02:57
Nature uses self-organizing systems.
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大自然是一个自组织系统。
02:59
Now in the 1980s, I happened to notice
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到了20世纪80年代,我碰巧发现
03:02
that if you look at an aerial photograph of an African village, you see fractals.
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在航拍的非洲部落照片中,存在着分形。
03:06
And I thought, "This is fabulous! I wonder why?"
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我惊叹道:“这简直太不可思议了!究竟是为什么呢?!”
03:10
And of course I had to go to Africa and ask folks why.
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于是我就去了非洲,去请教当地人这个问题。
03:12
So I got a Fulbright scholarship to just travel around Africa for a year
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我拿到了Fulbright奖学金,去非洲旅行一年,
03:18
asking people why they were building fractals,
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询问那儿的人为什么按照分形来盖房子。
03:20
which is a great job if you can get it.
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这工作真的很棒,如果你能得到的话。
03:22
(Laughter)
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(笑声)
03:23
And so I finally got to this city, and I'd done a little fractal model for the city
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后来我终于来到这座城市,那时我对城市分形建筑已构建了一些模型,
03:30
just to see how it would sort of unfold --
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想看看它与实际情况的符合情况--
03:33
but when I got there, I got to the palace of the chief,
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当我到了那儿,我去了酋长的宫殿,
03:36
and my French is not very good; I said something like,
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我的法语说得不太好,当时大概对他说:
03:39
"I am a mathematician and I would like to stand on your roof."
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“我是一名数学家,我想到你的屋顶上看看。”
03:42
But he was really cool about it, and he took me up there,
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对此他一点问题都没有,带我上到了屋顶,
03:45
and we talked about fractals.
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与我讨论起有关分形的问题。
03:46
And he said, "Oh yeah, yeah! We knew about a rectangle within a rectangle,
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他说:“对,对!我们知道一个方形可以嵌套一个方形,
03:49
we know all about that."
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我们知道有关的一切。”
03:51
And it turns out the royal insignia has a rectangle within a rectangle within a rectangle,
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后来我才知道,他们的皇家徽章图形就是由嵌套的方形构成的,
03:55
and the path through that palace is actually this spiral here.
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而宫殿的走道也是类似的螺旋形状。
03:59
And as you go through the path, you have to get more and more polite.
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当你沿着宫殿的走道往里走,你必须表现得越来越礼貌。
04:03
So they're mapping the social scaling onto the geometric scaling;
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他们将社会的层级结构跟房屋的几何结构联系起来;
04:06
it's a conscious pattern. It is not unconscious like a termite mound fractal.
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这些房屋的分形源自主动的构造,不像白蚁窝那样毫无意义。
04:11
This is a village in southern Zambia.
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这是赞比亚南部的一个村落,
04:13
The Ba-ila built this village about 400 meters in diameter.
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Ba-Ila人建造了这个直径约400米村子。
04:17
You have a huge ring.
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首先我们有一个很大的环形。
04:19
The rings that represent the family enclosures get larger and larger as you go towards the back,
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代表家族大小的环形,越往后走越大。
04:26
and then you have the chief's ring here towards the back
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最终属于首领(家族)的环形就在大环形的尾端,
04:30
and then the chief's immediate family in that ring.
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而首领的直系亲属在那个环形里。
04:33
So here's a little fractal model for it.
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这就是这个村落的分形模型。
04:34
Here's one house with the sacred altar,
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这是一幢拥有圣坛的房子,
04:37
here's the house of houses, the family enclosure,
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这是房子集合而成的“房子”,家族意义上的,
04:40
with the humans here where the sacred altar would be,
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原先圣坛所在的地方被人所占据,
04:43
and then here's the village as a whole --
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而这就是由先前层层叠叠房屋最终形成的村庄---
04:45
a ring of ring of rings with the chief's extended family here, the chief's immediate family here,
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一个由环形组成的环形组成的环形,首领的旁系亲属住这儿,直系亲属住这儿,
04:50
and here there's a tiny village only this big.
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在这儿,有一个只有丁点儿大的村庄。
04:53
Now you might wonder, how can people fit in a tiny village only this big?
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你也许会问,人怎么可能住进这么小的村子?
04:57
That's because they're spirit people. It's the ancestors.
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原因呢,在于住在这儿的居民是一些灵魂。他们是村民们的祖先。
05:00
And of course the spirit people have a little miniature village in their village, right?
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当然,这些灵魂居住的村子里也有一个更小的村子,对吧?
05:05
So it's just like Georg Cantor said, the recursion continues forever.
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所以就像康托说的,这样的递推将不断循环下去。
05:08
This is in the Mandara mountains, near the Nigerian border in Cameroon, Mokoulek.
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村庄Mokoulek坐落于曼达拉(Mandara)山脉中,接近尼日利亚与喀麦隆的交界处。
05:12
I saw this diagram drawn by a French architect,
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我看到这幅出自一位法国建筑师之手的图时,
05:15
and I thought, "Wow! What a beautiful fractal!"
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不禁惊叹:“哇!多么漂亮的分形!”
05:17
So I tried to come up with a seed shape, which, upon iteration, would unfold into this thing.
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于是我就试着画出这幅图的初始图形,一个经过不断重复变换能够转变成现在图案的初始图形。
05:23
I came up with this structure here.
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结果我画出了这个结构。
05:25
Let's see, first iteration, second, third, fourth.
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让我们来看一下:(这是)第一次循环,第二次,第三次,第四次……
05:29
Now, after I did the simulation,
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在我完成了这个模拟之后,
05:31
I realized the whole village kind of spirals around, just like this,
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我意识到这整个村庄就像螺旋一般盘旋环绕,就像这样,
05:34
and here's that replicating line -- a self-replicating line that unfolds into the fractal.
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而这就是那条不断复制的曲线--一条不断自我复制并最终延展成分形的螺旋。
05:40
Well, I noticed that line is about where the only square building in the village is at.
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我也注意到在那条曲线所在的附近,有着全村唯一的方形建筑。
05:45
So, when I got to the village,
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于是当我到达那个村子后,
05:47
I said, "Can you take me to the square building?
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我就问:“你可以把我带到那个方形建筑所在的地方去吗?”
05:49
I think something's going on there."
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“那儿一定有特别的故事。”
05:51
And they said, "Well, we can take you there, but you can't go inside
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他们回答:“我们可以带你到建筑的外围,但你不能进去,”
05:54
because that's the sacred altar, where we do sacrifices every year
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“因为那里面是圣坛,每年我们都举行祭祀,
05:57
to keep up those annual cycles of fertility for the fields."
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以祈祷每年土地的耕种、丰收遵守它固有的规律。”
06:00
And I started to realize that the cycles of fertility
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我开始意识到,土地耕种、收获的循环过程
06:02
were just like the recursive cycles in the geometric algorithm that builds this.
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就像建立这个村落所运用的几何算法的循环过程一般。
06:06
And the recursion in some of these villages continues down into very tiny scales.
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在一些村落中,这样的循环会始终持续直到很小的尺度上。
06:10
So here's a Nankani village in Mali.
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这是一个位于马里的村庄,名叫Nankani。
06:12
And you can see, you go inside the family enclosure --
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你可以看到,这些家族的层次结构,
06:15
you go inside and here's pots in the fireplace, stacked recursively.
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以及这些壁炉中按照一定次序叠放的瓦罐。
06:19
Here's calabashes that Issa was just showing us,
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这些是Issa展示给我们的葫芦,
06:23
and they're stacked recursively.
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它们也被“循环”地叠放着。
06:25
Now, the tiniest calabash in here keeps the woman's soul.
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在这最小的葫芦中,保存着一个女人的灵魂。
06:27
And when she dies, they have a ceremony
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当她死去时,人们会给她举行一个仪式,
06:29
where they break this stack called the zalanga and her soul goes off to eternity.
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仪式中人们打破这个叫做zalanga的葫芦堆,使她的灵魂走向永恒。
06:34
Once again, infinity is important.
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这再次说明,无限(永恒)是非常重要的。
06:38
Now, you might ask yourself three questions at this point.
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现在,有三个问题需待解决。
06:42
Aren't these scaling patterns just universal to all indigenous architecture?
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第一,这些图案在原生态的建筑中是普遍存在的吗?
06:46
And that was actually my original hypothesis.
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在我的最初假设中答案是肯定的。
06:48
When I first saw those African fractals,
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当我第一次看到那些非洲的分形建筑时,
06:50
I thought, "Wow, so any indigenous group that doesn't have a state society,
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我想:“哇,那些没有形成正规国家社会与等级制度的土著族群,
06:54
that sort of hierarchy, must have a kind of bottom-up architecture."
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一定都有那种‘自下而上’的建筑形式咯!”
06:57
But that turns out not to be true.
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然而事实并非如此。
06:59
I started collecting aerial photographs of Native American and South Pacific architecture;
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在我收集的美洲土著、南太平洋建筑的航拍照片中,
07:03
only the African ones were fractal.
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只有非洲建筑具有分形结构。
07:05
And if you think about it, all these different societies have different geometric design themes that they use.
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如果你仔细回想,会发现所有这些社会都具有不同的几何设计作为它们的主题。
07:11
So Native Americans use a combination of circular symmetry and fourfold symmetry.
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就如美洲土著用的是一种圆形对称和四方对称的组合图案,
07:17
You can see on the pottery and the baskets.
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你可以在陶器和篮子上看到它们。
07:19
Here's an aerial photograph of one of the Anasazi ruins;
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这是部分Anasazi废墟(Anasazi ruins)的航拍照片,
07:22
you can see it's circular at the largest scale, but it's rectangular at the smaller scale, right?
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你可以发现,粗略看时它呈圆形,而细看时它是方形的,对吧?
07:27
It is not the same pattern at two different scales.
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对于这种图形,在不同的尺度上,它有着不同的结构形态。
07:31
Second, you might ask,
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第二点,你也许会奇怪,
07:32
"Well, Dr. Eglash, aren't you ignoring the diversity of African cultures?"
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“Eglash博士(演讲者),你是不是忽略了非洲文化的多样性呢?”
07:36
And three times, the answer is no.
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我坚决地告诉你:不。
07:38
First of all, I agree with Mudimbe's wonderful book, "The Invention of Africa,"
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首先,我同意Mudimbe《非洲的发明》一书的说法,
07:42
that Africa is an artificial invention of first colonialism,
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即非洲是第一次殖民主义及殖民抗争的
07:45
and then oppositional movements.
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非自然的产物。
07:47
No, because a widely shared design practice doesn't necessarily give you a unity of culture --
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但分形建筑在非洲的普遍性却与此无太大关联。建筑形态的普遍性不代表文化的一致性---
07:52
and it definitely is not "in the DNA."
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DNA绝没有决定人们的文化须是一致的。
07:55
And finally, the fractals have self-similarity --
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最后一点,分形是具有自我相似性的---
07:57
so they're similar to themselves, but they're not necessarily similar to each other --
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可是它们只需自我相似,互相之间却未必是相似的---
08:01
you see very different uses for fractals.
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对于分形的不同应用有很多种,
08:03
It's a shared technology in Africa.
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在非洲这是一种众人皆知的技术。
08:06
And finally, well, isn't this just intuition?
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再回想一下,恩,难道这不是某种直觉产生的技术吗?
08:09
It's not really mathematical knowledge.
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它恐怕没有运用到什么真正意义上的数学知识。
08:11
Africans can't possibly really be using fractal geometry, right?
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非洲人不可能真的在运用“分形几何学”,对吧?
08:14
It wasn't invented until the 1970s.
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因为分形几何学直到20世纪70年代才被发明出来。
08:17
Well, it's true that some African fractals are, as far as I'm concerned, just pure intuition.
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的确,就我理解,一些非洲的分形不过来源于单纯的直觉罢了。
08:22
So some of these things, I'd wander around the streets of Dakar
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对于这些东西,如果我在达喀尔(Dakar)的街上闲逛
08:25
asking people, "What's the algorithm? What's the rule for making this?"
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并且问当地人“有什么算法吗?构造这些的规则是什么?”,
08:28
and they'd say,
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他们会回答说:
08:29
"Well, we just make it that way because it looks pretty, stupid." (Laughter)
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“嘿,我们这样做因为它们好看,傻瓜。”(笑声)
08:32
But sometimes, that's not the case.
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但有些时候,情况则不尽相同。
08:35
In some cases, there would actually be algorithms, and very sophisticated algorithms.
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对于一些图形的绘制,算法是必要的,而且是非常复杂的算法。
08:40
So in Manghetu sculpture, you'd see this recursive geometry.
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在Manghetu雕塑中,你可以看到这样有重复结构的几何图形。
08:43
In Ethiopian crosses, you see this wonderful unfolding of the shape.
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在Ethiopian十字中,有这样美妙的延展而成的图形。
08:48
In Angola, the Chokwe people draw lines in the sand,
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在安哥拉,Chokwe人在沙中绘制图线,
08:52
and it's what the German mathematician Euler called a graph;
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而这就是德国数学家欧拉(Euler)称作“图”(graph)的东西。
08:55
we now call it an Eulerian path --
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现在,我们称之为欧拉路径(Eulerian path)---
08:57
you can never lift your stylus from the surface
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你的笔尖始终不能离开纸平面,
08:59
and you can never go over the same line twice.
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并且不能穿过同一条线两次。
09:02
But they do it recursively, and they do it with an age-grade system,
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Chokwe人反复学习绘图,并根据年龄区分他们所学的内容:
09:05
so the little kids learn this one, and then the older kids learn this one,
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因而幼龄的孩子学习这个,稍年长的学习这个,
09:08
then the next age-grade initiation, you learn this one.
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再下一个年龄层的,学习这个。
09:11
And with each iteration of that algorithm,
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随着算法的迭代,
09:14
you learn the iterations of the myth.
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你将瞥见奇妙事物的发生发展,
09:16
You learn the next level of knowledge.
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并习得更深层次的知识。
09:19
And finally, all over Africa, you see this board game.
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再说一点,在整个非洲,你都可以看到这种棋牌游戏。
09:21
It's called Owari in Ghana, where I studied it;
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在我研究它的地方,加纳(Ghana), 它被称作Owari.
09:24
it's called Mancala here on the East Coast, Bao in Kenya, Sogo elsewhere.
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在东海岸它被称为Mancala,在肯尼亚叫Bao,在其他地方则是Sogo.
09:29
Well, you see self-organizing patterns that spontaneously occur in this board game.
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在这个游戏中,你会发现自组织图案很自然的产生 。
09:34
And the folks in Ghana knew about these self-organizing patterns
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加纳人知道并了解它们,
09:37
and would use them strategically.
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并有策略地应用它们。
09:39
So this is very conscious knowledge.
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对他们来说,这是一种有意义(而非不明不白获取)的知识。
09:41
Here's a wonderful fractal.
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这儿有一个美丽的分形。
09:43
Anywhere you go in the Sahel, you'll see this windscreen.
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在萨赫勒(Sahel)地区,你到哪儿都可看到这样的篱笆。
09:47
And of course fences around the world are all Cartesian, all strictly linear.
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人们通常认为篱笆在全世界都是"笛卡尔"式的,严格的直线型排列。
09:51
But here in Africa, you've got these nonlinear scaling fences.
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但在非洲,你会发现这些不笔直排列的篱笆。
09:55
So I tracked down one of the folks who makes these things,
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我找到了一个做这种篱笆的人,
09:57
this guy in Mali just outside of Bamako, and I asked him,
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他住在Bamako外的Mali(马里).我问他:
10:01
"How come you're making fractal fences? Because nobody else is."
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“为什么你做分形的篱笆,而别人都没有?”
10:03
And his answer was very interesting.
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他的回答相当有趣。
10:05
He said, "Well, if I lived in the jungle, I would only use the long rows of straw
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他说:“如果我住在丛林里,我会只用那些长麦秆来做篱笆,
10:10
because they're very quick and they're very cheap.
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因为它们易完成,并且很廉价。
10:12
It doesn't take much time, doesn't take much straw."
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不需要花费太多时间,也不需要太多麦秆”
10:15
He said, "but wind and dust goes through pretty easily.
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他继续道:“但是风沙和尘土很容易穿过那些篱笆。
10:17
Now, the tight rows up at the very top, they really hold out the wind and dust.
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而如果篱笆顶部(的麦秆)排列比较紧密,防风尘的效 果会非常好。
10:21
But it takes a lot of time, and it takes a lot of straw because they're really tight."
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但制作它们花费很多时间,也需要很多麦秆,因为它们排列真的很紧密。
10:26
"Now," he said, "we know from experience
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从经验中我们也知道,
10:28
that the farther up from the ground you go, the stronger the wind blows."
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从地面往上越靠近篱笆顶部,风力越强劲。”
10:33
Right? It's just like a cost-benefit analysis.
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他说的很正确,是吧?这就像是成本效益分析。
10:36
And I measured out the lengths of straw,
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于是我测量了篱笆麦秆的长度,
10:38
put it on a log-log plot, got the scaling exponent,
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把数据放到重对数坐标中,得到了一个标度指数,
10:40
and it almost exactly matches the scaling exponent for the relationship between wind speed and height
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这个标度指数几乎跟风力工程手册中
10:45
in the wind engineering handbook.
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风速与高度的标度指数完全匹配。
10:46
So these guys are right on target for a practical use of scaling technology.
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所以,这些当地人把分形很好地应用在了实际中。
10:51
The most complex example of an algorithmic approach to fractals that I found
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在众多形成分形的算法中,我所发现的最为复杂的
10:56
was actually not in geometry, it was in a symbolic code,
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并不是几何图形的算法,而是这个符号代码的,
10:58
and this was Bamana sand divination.
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用于Bamana沙地占卜。
11:01
And the same divination system is found all over Africa.
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类似的占卜系统在整个非洲都可见到,
11:04
You can find it on the East Coast as well as the West Coast,
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东、西海岸都有。
11:09
and often the symbols are very well preserved,
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这些符号通常都被良好的保存下来,
11:11
so each of these symbols has four bits -- it's a four-bit binary word --
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每个符号分为四部分,可看做四个二进制位组成的单元---
11:17
you draw these lines in the sand randomly, and then you count off,
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你在沙地里随意画下这样的线段,然后数一下,
11:22
and if it's an odd number, you put down one stroke,
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(一行中)如果有奇数条线段,划下一条线,
11:24
and if it's an even number, you put down two strokes.
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而如果有偶数条,划两条线。
11:26
And they did this very rapidly,
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他们非常快速的完成这工作,
11:29
and I couldn't understand where they were getting --
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可我不明白他们究竟做了些什么---
11:31
they only did the randomness four times --
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他们仅仅随意画四行线段---
11:33
I couldn't understand where they were getting the other 12 symbols.
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我不知道剩下的十二个(占卜)符号他们是怎样得来的,
11:35
And they wouldn't tell me.
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而他们也不愿意告诉我。
11:37
They said, "No, no, I can't tell you about this."
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他们说:“不,不,我们不能告诉你这些。”
11:39
And I said, "Well look, I'll pay you, you can be my teacher,
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我回答说:“这样吧,你们可以做我的老师,我付你们工钱,
11:41
and I'll come each day and pay you."
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我每天都上你们这儿来,并每日付薪水。”
11:43
They said, "It's not a matter of money. This is a religious matter."
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他们说:“这不是钱的问题。这涉及到宗教与信仰。”
11:46
And finally, out of desperation, I said,
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最终,我绝望地说道:
11:47
"Well, let me explain Georg Cantor in 1877."
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“好吧,那最后请让我向你们介绍一下康托。(Georg Cantor)”
11:50
And I started explaining why I was there in Africa,
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于是我开始向他们解释我来非洲的原因。
11:54
and they got very excited when they saw the Cantor set.
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当他们听说康托集时,显得异常兴奋。
11:56
And one of them said, "Come here. I think I can help you out here."
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他们中的一个说道:“来吧,我想我能解决你的问题。”
12:00
And so he took me through the initiation ritual for a Bamana priest.
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于是他带我完成了Bamana教的入会仪式。
12:05
And of course, I was only interested in the math,
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当然,我只对其中的数学问题感兴趣。
12:07
so the whole time, he kept shaking his head going,
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整个过程中,他始终摇头晃脑,说着
12:09
"You know, I didn't learn it this way."
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“你知道吗,我原来可不知道这其中的奥秘。”
12:10
But I had to sleep with a kola nut next to my bed, buried in sand,
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而我得和埋在床边沙子中的可乐树果子(kola nut)睡一块儿,
12:14
and give seven coins to seven lepers and so on.
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将七枚硬币给予七个麻风病人,等等。
12:17
And finally, he revealed the truth of the matter.
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最终,他向我揭示了那些符号的奥秘。
12:22
And it turns out it's a pseudo-random number generator using deterministic chaos.
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事实是,那些符号产生自确定性混沌---一个伪随机过程。
12:26
When you have a four-bit symbol, you then put it together with another one sideways.
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你将一个已有的4位(four-bit)的符号与另一个放在一起。
12:32
So even plus odd gives you odd.
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于是偶数加奇数得奇数;
12:34
Odd plus even gives you odd.
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奇数加偶数得奇;
12:36
Even plus even gives you even. Odd plus odd gives you even.
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偶数加偶数得偶;奇数加奇数得偶。
12:39
It's addition modulo 2, just like in the parity bit check on your computer.
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这是一位加和的二进制数,就像计算机奇偶校验中的一位加和编码一样。
12:43
And then you take this symbol, and you put it back in
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然后你用新得到的符号替换原有的,
12:47
so it's a self-generating diversity of symbols.
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于是你就“自我繁衍”出一系列的符号。
12:49
They're truly using a kind of deterministic chaos in doing this.
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他们真真确确在运用确定性混沌的理论。
12:53
Now, because it's a binary code,
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由于这些是二值码,
12:55
you can actually implement this in hardware --
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事实上你可以将他们运用到硬件中---
12:57
what a fantastic teaching tool that should be in African engineering schools.
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多么有趣的案例,真该运用到非洲的工程学校的教学中。
13:02
And the most interesting thing I found out about it was historical.
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对于这些符号,我发现的最有趣的事还是关于它们的历史。
13:05
In the 12th century, Hugo of Santalla brought it from Islamic mystics into Spain.
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在十二世纪,桑塔拉的休(Hugo of Santalla)将来源于伊斯兰神话的它们带到西班牙。
13:11
And there it entered into the alchemy community as geomancy:
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在那儿,它进入炼金术士的团体,用于看风水:
13:17
divination through the earth.
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通过泥土来占卜(抓沙散地,按其所成像以断吉凶)。
13:19
This is a geomantic chart drawn for King Richard II in 1390.
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这是一幅在1390年为理查二世(King Richard II)绘制的占卜图。
13:24
Leibniz, the German mathematician,
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德国数学家莱布尼兹(Leibniz)
13:27
talked about geomancy in his dissertation called "De Combinatoria."
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在他名为"De Combinatoria"的论文中谈论到了泥土占卜。
13:31
And he said, "Well, instead of using one stroke and two strokes,
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在文章中他说:“我们不使用一条或两条的划线
13:35
let's use a one and a zero, and we can count by powers of two."
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而是使用数字0和1,于是我们可以把它们作二进制数来对待。”
13:39
Right? Ones and zeros, the binary code.
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这不就是吗?由很多0和1组成了二进制码。
13:41
George Boole took Leibniz's binary code and created Boolean algebra,
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布尔(George Boole)运用莱布尼兹的二进制码创造了布尔代数(Boolean algebra),
13:44
and John von Neumann took Boolean algebra and created the digital computer.
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约翰.冯.诺依曼(John von Neumann)则利用布尔代数创造了电脑.
13:47
So all these little PDAs and laptops --
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因而所有这些小器件---PDA,便携式电脑---
13:50
every digital circuit in the world -- started in Africa.
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所有世间的数字电路---都起源于非洲。
13:53
And I know Brian Eno says there's not enough Africa in computers,
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据我所知布莱恩·伊诺(Brian Eno)说非洲在数字化进程中没有多大贡献;
13:58
but you know, I don't think there's enough African history in Brian Eno.
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而我认为事实是Brian Eno脑中没有足够的非洲历史。
14:03
(Laughter) (Applause)
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(掌声)
14:06
So let me end with just a few words about applications that we've found for this.
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请让我简单地用这些分形的实际应用结束这场演讲。
14:10
And you can go to our website,
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你也可以浏览我们的网站,
14:12
the applets are all free; they just run in the browser.
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程序都是免费的,可以直接运行,
14:14
Anybody in the world can use them.
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世界上的任何人都可以使用它们。
14:16
The National Science Foundation's Broadening Participation in Computing program
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The National Science Foundation's Broadening Participation in Computing program(某基金会)
14:21
recently awarded us a grant to make a programmable version of these design tools,
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近日授予我们一笔资金,来将这些图形设计工具制作成可编辑版本,
14:28
so hopefully in three years, anybody'll be able to go on the Web
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顺利的话,在三年内,所有人都能在网上
14:30
and create their own simulations and their own artifacts.
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创造出属于自己的分形与艺术品。
14:33
We've focused in the U.S. on African-American students as well as Native American and Latino.
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在美国,我们特别关注了非洲裔美国学生、美国土著居民和拉丁美洲人,
14:38
We've found statistically significant improvement with children using this software in a mathematics class
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并通过统计发现在数学课中使用这款软件的孩子与一批作为对照组、
14:44
in comparison with a control group that did not have the software.
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不使用该软件的孩子相比,学术表现有了极大提高。
14:47
So it's really very successful teaching children that they have a heritage that's about mathematics,
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因而教授学生,告知他们自己所具有的数学传统,是非常有意义的,
14:53
that it's not just about singing and dancing.
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而不仅仅教他们唱歌、跳舞。
14:57
We've started a pilot program in Ghana.
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我们在加纳启动了一个试验项目。
15:00
We got a small seed grant, just to see if folks would be willing to work with us on this;
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我们先提供一小笔种子资金,看人们是否愿意与我们合作;
15:05
we're very excited about the future possibilities for that.
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对于未来(更大规模)的合作,我们都充满期待。
15:08
We've also been working in design.
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我们也在设计方面不断努力。
15:10
I didn't put his name up here -- my colleague, Kerry, in Kenya, has come up with this great idea
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我没把我这位同事的名字放上来---肯尼亚的Kerry,是他想出了这个绝妙的点子:
15:15
for using fractal structure for postal address in villages that have fractal structure,
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在具有分形结构的村落中应用具有分形结构的邮政网络,
15:20
because if you try to impose a grid structure postal system on a fractal village,
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因为一个方格状的邮递系统很难适应
15:24
it doesn't quite fit.
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分形的村落结构。
15:26
Bernard Tschumi at Columbia University has finished using this in a design for a museum of African art.
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哥伦比亚大学的Bernard Tschumi运用分形(及其衍生品)完成了对非洲艺术博物馆的设计。
15:31
David Hughes at Ohio State University has written a primer on Afrocentric architecture
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俄亥俄州立大学的David Hughes完成了一本有关非洲中心架构(Afrocentric architecture)的入门读物,
15:39
in which he's used some of these fractal structures.
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在其中他运用到了一些分形结构。
15:41
And finally, I just wanted to point out that this idea of self-organization,
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最后,我想指出这种自组织(self-organization)的思想---
15:46
as we heard earlier, it's in the brain.
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我之前也提到过---是牢固存在大脑里的。
15:48
It's in the -- it's in Google's search engine.
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它也存在于谷歌(Google)的搜索引擎中。
15:53
Actually, the reason that Google was such a success
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事实上,谷歌能够获得如此巨大的成功,
15:55
is because they were the first ones to take advantage of the self-organizing properties of the web.
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就在于它第一个利用了网络的这种自组织性质。
15:59
It's in ecological sustainability.
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它体现于生态的可持续性,
16:01
It's in the developmental power of entrepreneurship,
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体现于企业的发展力,
16:03
the ethical power of democracy.
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也体现于民主思想的道德约束力。
16:06
It's also in some bad things.
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它也体现在一些坏的事情当中。
16:08
Self-organization is why the AIDS virus is spreading so fast.
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自我组织是艾滋病毒传播如此迅速的原因。
16:11
And if you don't think that capitalism, which is self-organizing, can have destructive effects,
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此外,如果你不认为具有自组织性质的资本主义能产生毁灭性的影响,
16:15
you haven't opened your eyes enough.
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那么你还没有真正看清这个世界。
16:17
So we need to think about, as was spoken earlier,
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因而我们需要思考,如我之前所说的,
16:21
the traditional African methods for doing self-organization.
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非洲传统的自组织的方式。
16:23
These are robust algorithms.
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这些才是强健的算法(方法)。
16:26
These are ways of doing self-organization -- of doing entrepreneurship --
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这些才是进行自组织的方式---发展企业的方式---
16:29
that are gentle, that are egalitarian.
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它们温和、平缓。
16:31
So if we want to find a better way of doing that kind of work,
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因此如果我们想寻找一个更好的涉及此类工作的方式,
16:35
we need look only no farther than Africa to find these robust self-organizing algorithms.
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只需从非洲就能找寻到这些强健的自组织算法。
16:40
Thank you.
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谢谢大家。
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