12.《微观动机与宏观行为》Micro Motivations and Macro Behaviour

The book we are talking about today is called Micro Motives and Macro Behaviour. This book is the masterpiece of the famous game theory guru, Thomas Schelling. An interesting insight from this book is that, whether we subjectively want to change the world or not, in reality, every choice we make, each of us, has the potential to affect the world. Many users have added many interesting examples in response to this insight.
I remember Mr Hu Shih's autobiography where he wrote that a person's actions can have an impact on society. For example, a speaker pronounced the o sound strangely, and Mr Hu Shih found it interesting and learned the pronunciation. Later, as a teacher, Mr Hu Shih passed on the strange pronunciation to his students, who in turn may have influenced many more people. And so, such a simple act spread through the group, it really didn't occur to me. As the book says, every choice you make has a relationship with others and will not only affect them, but most likely the whole community.
You might think, "Mr. Hu Shih is a celebrity, that's why he has so much influence, and an unconscious action by us ordinary people shouldn't have much impact, right? It's not really true.
When crossing the road, a large group of pedestrians were waiting for the red light, all obeying the traffic rules. But then, all of a sudden, an impatient person takes the lead and runs the red light, and the others take a look and follow suit. You see, a single, perhaps subconscious action by an ordinary person can influence the choices of a large group of people.
Very often, gaming behaviour also acts as an amplifier. Three or two naughty children in the class deliberately isolate another classmate, and the other classmates reduce their interaction with that classmate out of a sense of "not offending", and as a result that child is really isolated. It is necessary to intervene from outside the system (the teacher).
Gaming behaviour is ubiquitous in life and can have both good and bad consequences. Whether good or bad, once the behaviour has been initiated it is difficult to stop on its own and requires greater external intervention. So, to avoid bad gaming cycles starting, it is important to limit behaviour that appears to be beneficial to the individual but harmful to the system from the outset.
It is surprising that the type of car security lock we choose for ourselves can affect the probability of our neighbour's car being stolen. Why is this?
The first type of anti-theft lock is one that locks onto the steering wheel of the car and also emits a fluorescent light. This is a warning to car thieves that my car is locked and very bad to steal. This warning has a negative external effect because the subtext is that "the car next to the unlocked car is better", which is detrimental to the safety of other cars.
The second type of lock is fitted to a hidden part of the car, so that if the car is stolen, the police can follow the signal from the lock and catch the thief. This type of lock has a positive external effect. Because the lock is installed in a hidden location, the thief cannot tell if the car he wants to steal has an anti-theft lock, and if it does, they will be caught if they steal it, so they dare not do it easily and reduce the number of crimes. This also increases the security of owners of cars without locks.
译文：
 今天要聊的这本书，叫《微观动机与宏观行为》。这本书是著名博弈论大师托马斯·谢林的代表作。这本书里有个有趣的洞察，就是，不管我们主观上是不是想改变这个世界，但实际上，我们每个人的每次选择，都有可能影响到这个世界。很多用户针对这个洞察，补充了很多有趣的例子。
记得胡适先生的自传里写到，一个人的行为会对社会产生影响。比如，一位演讲者的o音发音很奇怪，胡适先生觉得很有趣就学会了这个发音，后来，胡适先生作为老师，又把这个奇怪的发音传授给了他的学生们，而他的学生又可能影响到更多的人。于是，这样一个简单的举动就在群体中扩散，真是没有想到。就像这本书说的，你的每个选择，都与别人有关系，不但会影响到别人，而且很有可能会影响到整个社会。
你可能会觉得，胡适先生是一个名人啊，所以才有这么大的影响力，而我们普通人的一个无意识的动作，应该就没有什么影响吧？还真不一定。
过马路的时候，一大群行人在等红灯，都很遵守交通规则。但这时，忽然有个心急的人带头闯红灯，其他人一看，也就跟着闯红灯。你看，一个普通人的一个可能下意识的举动，就能影响一大群人的选择。
很多时候，博弈行为还起着放大器的作用。班上三两个调皮的小孩儿，刻意孤立另一个同学，别的同学出于“不得罪人”的心态也减少了和该同学的交往，结果那个小孩儿真的就被孤立了，这时候，系统内（孩子们）就形成一个加强循环，没办法解套，系统外（老师）的介入就非常必要。
博弈行为在生活里无处不在，造成的结果有好有坏。无论好坏，行为一旦启动就难以自行终止，需要靠更大外力来强行干预。所以，为了避免坏的博弈循环启动，从一开始就要对看起来对个体有利但是对系统有害的行为加以限制。
我们自己选择什么样的汽车防盗锁，竟然会影响到邻居的车被偷的概率。这是为什么呢？
第一种防盗锁是锁在汽车方向盘上的，而且还会发出荧光。这就是在警告偷车贼，我的车是上了锁的，很不好偷。这种警告就会产生负外部效应，因为它的潜台词就是“旁边没装锁的车更好偷”，这对其他车的安全是种伤害。
第二种防盗锁是装在车的隐秘部位，如果车被偷了，警察就可以跟踪防盗锁发出的信号，抓住偷车贼。这种锁就具有正外部效应。因为锁装在隐秘的位置，偷车贼也没法判断他要偷的车有没有装防盗锁，万一装了的话，他们去偷就会被抓，所以他们不敢轻易下手，减少作案次数。这样没装防盗锁的车主的安全度也提高了。