And how do the tiny cells in your brain give rise to the complex thoughts,

而大腦內的微小細胞們又是如何組成複雜的思想

memories,

記憶

and consciousness that are you?

以及身為「你自己」的意識？

Oddly enough, those questions have the same general answer:

說也奇怪，這些問題有同樣普遍的答案

emergence,

稱做「湧現」

or the spontaneous creation of sophisticated behaviors and functions

即由小單元自然生成的大群體

from large groups of simple elements.

表現出來的複雜行為和功能

Like many animals, fish stick together in groups,

就像許多動物一樣，魚也會形成一個群體

but that's not just because they enjoy each other's company.

但這並不僅僅是因為牠們喜歡彼此的陪伴

It's a matter of survival.

而是攸關生存的事

Schools of fish exhibit complex swarming behaviors

魚群表現出複雜的群聚行為

that help them evade hungry predators,

來幫助他們躲避飢餓的掠食者

while a lone fish is quickly singled out as easy prey.

同時落單的魚容易快速的被選為獵物

So which brilliant fish leader is the one in charge?

所以哪條優秀的魚是看管魚群的領頭魚呢？

Actually, no one is,

事實上，大家都不是領頭魚

and everyone is.

反而每隻魚都是

So what does that mean?

這是什麼意思呢？

While the school of fish is elegantly twisting, turning, and dodging sharks

當魚群以看似從容協調的樣子

in what looks like deliberate coordination,

優雅地扭動，轉彎，還有躲避鯊魚的時候

each individual fish is actually just following two basic rules

魚群裡的每條魚事實上只遵循兩個

that have nothing to do with the shark:

和鯊魚一點關係都沒有的基本原則

one, stay close, but not too close to your neighbor,

第一，和鄰近的魚保持適當的距離

and two, keep swimmming.

第二，持續游動

As individuals, the fish are focused on the minutiae of these local interactions,

做為個體，每條魚只專注於這些局部交互作用的細節

but if enough fish join the group, something remarkable happens.

不過如果足夠多的魚加入群體，有些值得注意的事發生了

The movement of individual fish is eclipsed by an entirely new entity:

每條魚的行為會隱藏在全新的群體中

the school, which has its own unique set of behaviors.

而這樣的群體擁有自己獨特的行為模式

The school isn't controlled by any single fish.

魚群並不被任何單獨的魚控制

It simply emerges if you have enough fish following the right set of local rules.

它僅僅出現在夠多的魚遵循適當的局部行為的時候

It's like an accident that happens over and over again,

彷彿不斷發生的偶發事件一樣

allowing fish all across the ocean to reliably avoid predation.

使橫越海洋的魚確實免於掠食者的傷害

And it's not just fish.

這並不只發生在魚身上

Emergence is a basic property of many complex systems of interacting elements.

「湧現」是許多複雜系統內反應單元的基本特性

For example, the specific way in which millions of grains of sand

舉例來說，幾百萬粒的沙子以特定的方式

collide and tumble over each other

聚集和翻動

almost always produces the same basic pattern of ripples.

幾乎每次都在沙灘上製造了相同的基本紋路

And when moisture freezes in the atmosphere,

當水分在空氣中凍結時

the specific binding properties of water molecules

水分子間的結合性質

reliably produce radiating lattices that form into beautiful snowflakes.

製造出了漂亮雪花中的放射狀晶體結構

What makes emergence so complex

是什麼讓「湧現」如此複雜

is that you can't understand it by simply taking it apart,

以至於你無法僅僅像是研究汽車的引擎那樣

like the engine of a car.

單純將它拆開來理解？

Taking things apart is a good first step to understanding a complex system.

要理解一個複雜的系統，將它拆成小部份分析是最好的方式

But if you reduce a school of fish to individuals,

但你如果將一群魚拆成每個個體

it loses the ability to evade predators,

牠就失去了躲避掠食者的能力

and there's nothing left to study.

也沒留下任何可供研究的東西

And if you reduce the brain to individual neurons,

如果你將大腦拆成一個個神經元

you're left with something that is notoriously unreliable,

你會發現這些東西是出了名的不可靠

and nothing like how we think and behave,

至少在大部份時間內，看不出它們是如何造就

at least most of the time.

我們的思想和行為

Regardless, whatever you're thinking about right now

無論如何，你現在腦中所想的任何事情

isn't reliant on a single neuron lodged in the corner of your brain.

都不只受你頭腦裡的單一神經元影響

Rather, the mind emerges from the collective activities

相反地，心智活動的形成是來自於

of many, many neurons.

許多神經元的集體活動

There are billions of neurons in the human brain,

人腦中有幾十億的神經元細胞

and trillions of connections between all those neurons.

在這些神經細胞間還有幾兆條的連線

When you turn such a complicated system like that on,

當你觸發了像這樣複雜的系統的時候

it could behave in all sorts of weird ways, but it doesn't.

它可能會以各種奇怪的方式展現，但其實沒有

The neurons in our brain follow simple rules, just like the fish,

我們大腦裡的神經元就像魚群裡的魚一樣，也只遵循基本的規則

so that as a group, their activity self-organizes into reliable patterns

當它們集合成群，它們之間的作用會自組織成可靠的模式

that let you do things like recognize faces,

讓你可以做一些事情，像是辨識人臉

successfully repeat the same task over and over again,

或是不斷的重複同樣的工作

and keep all those silly little habits that everyone likes about you.

以及保存那些能讓大家知道是「你」的糊塗小習慣

So, what are the simple rules when it comes to the brain?

所以大腦裡的神經元運作的基本原則是什麼呢？

The basic function of each neuron in the brain

大腦中每個神經元的基本功能

is to either excite or inhibit other neurons.

就是激活或是抑制其他神經元

If you connect a few neurons together into a simple circuit,

如果你將少數幾個神經元連成一個簡單迴路

you can generate rhythmic patterns of activity,

就會產生一個有規律的活動模塊

feedback loops that ramp up or shut down a signal,

回饋給迴路增生訊號或解除訊號的資訊

coincidence detectors,

同時偵測

and disinhibition,

和解除抑制

where two inhibitory neurons can actually activate another neuron

也就是兩個被抑制的神經元在移除抑制因素後

by removing inhibitory brakes.

就能激活其他神經元了

As more and more neurons are connected,

當越來越多神經元連結

increasingly complex patterns of activity emerge from the network.

逐漸複雜的活動模塊從神經網路中出現

Soon, so many neurons are interacting in so many different ways at once

很快的，許多神經元在同一時間以各種不同的方式互動

that the system becomes chaotic.

使整個系統混亂不已

The trajectory of the network's activity cannot be easily explained

神經網路的活動途徑無法輕易的

by the simple local circuits described earlier.

用剛剛所描述的局部迴路來說明

And yet, from this chaos, patterns can emerge,

不過，因為這樣的混亂，使得這些模塊得以形成

and then emerge again and again in a reproducible manner.

並不斷的複製再生

At some point, these emergent patterns of activity

某方面而言，這些新生的活動模塊

become sufficiently complex,

已變得足夠複雜

and curious to begin studying their own biological origins,

且難以理解，以致於不能研究它們的生物性起源

not to mention emergence.

更不用說是「湧現」現象的起源了

And what we found in emergent phenomena at vastly different scales

我們在許多尺度下發現的湧現現象

is that same remarkable characteristic as the fish displayed:

就和魚群所展現出來的特性一樣值得注意：

That emergence doesn't require someone or something to be in charge.

「湧現」這個現象並不需要任何人或物來主導

If the right rules are in place,

如果適當的規則發生在適合的地方

and some basic conditions are met,

並吻合基本條件

a complex system will fall into the same habits over and over again,

此時就會產生一個複雜的系統，並且不斷以相同的規律運作，

turning chaos into order.

將混亂轉為規律

That's true in the molecular pandemonium that lets your cells function,

這些都是確實的例子：分子的混亂使我們的細胞得以運行

the tangled thicket of neurons that produces your thoughts and identity,

糾纏的神經叢造就了我們的思想與個性

your network of friends and family,

我們和家人朋友間的連結

all the way up to the structures and economies of our cities across the planet.

一路向上擴張到組成我們這個城市的政經結構，進而遍及整個地球