The new convergence of biology and economy has been helped by a common methodology — game theory. John Maynard Smith, a professor of biology at the University of Sussex, in Britain, was the first to effectively apply the economist’s habit of playing a “game” with competing strategies to evolutionary mysteries. The only difference is that the economic games reward winners with money while evolutionary games reward winners with chance to survive and breed. One game in particular has proved especially informative in both disciplines: the prisoner’s dilemma.
A dramatized version of the game runs as follows: two guilty accomplices are held in separate cells and interrogated by the police. Each is faced with a dilemma. If they both confess (or “defect”), they will both go to jail for three years. If they both stay silent (or “cooperate”), they will both go to jail for a year on a lesser charge that the police can prove. But if one confesses and the other does not, the former will walk free on an agreement, while the cooperator, who stayed silent, will get a five-year sentence.
Assuming that they have not discussed the dilemma before they were arrested, can each trust his accomplice to stay silent? If not, he should defect and reduce his sentence from five to three years. But even if he can rely on his partner to cooperate, he is still better off if he defects, because that reduces his sentence from three years to none at all. So each will reason that the right thing to do is to defect, which results in three years for each of them. In the language of game theorists, individually rational strategies result in a collectively irrational outcome.
Biologists were interested in the prisoner’s dilemma as a model for the evolution of cooperation. Under what conditions, they wanted to know, would it pay an animal to evolve a strategy based on cooperation rather than defection? They discovered that the bleak message of the prisoner’s dilemma need not obtain if the game is only one in a long series — played by students, researchers, or computers, for points rather than years in jail. Under these circumstances the best strategy is to cooperate on the first trial and then do whatever the other guy did last time. This strategy became known as tit-for-tat. The threat of retaliation makes defection much less likely to pay.
Robert Alfred, a political scientist, and William Hamilton, a biologist, both at the University of Michigan, discovered by public tournament that there seems to be no strategy that beats tit-for-tat. Tit-for-two-tats — that is, cooperate even if the other defects once, but not if he defects twice — comes close to beating it, but of hundreds of strategies that have been tried, none works better.
1.What is game theory?
2.The two guilty accomplices mentioned in Para. 2 are （ ）.
3.For the worst situation, what is the total year of the two accomplices’ sentence?
4.What are the biologists’ findings for the cooperation strategy?
5.What does tit-for-two-tats mean?
问题1选项
A.The theory to play games.
B.It means playing a “game” with competing strategies to evolutionary mysteries.
C.It is a methodology applied to both economy and evolution.
D.It helps people to survive.
问题2选项
A.part of a drama
B.used to find a simpler way to explain the game theory
C.to explain how the police punish the crime
D.to explain how the game theory come into being
问题3选项
A.Three years.
B.Five years.
C.Six years.
D.Zero
问题4选项
A.There is no result since the game is in a long series.
B.People would like to cooperate.
C.People would like to cooperate and what they do next time depends.
D.People would like not to cooperate.
问题5选项
A.When one gives tit, the other will give two tats in response.
B.When one gives two tats, the other will give tit in response.
C.Tit-for-two-tats develops from tit-for-tat.
D.When cooperation fails the first time, there will be another chance.
第1题:C
第2题:B
第3题:C
第4题:C
第5题:D
第1题:
【选项释义】
What is game theory? 博弈论是什么？
A. The theory to play games. A. 玩游戏的理论。
B. It means playing a “game” with competing strategies to evolutionary mysteries. B. 它是指用竞争策略“玩游戏”来解决进化谜团。
C. It is a methodology applied to both economy and evolution. C. 它是一种同时应用于经济和进化领域的方法论。
D. It helps people to survive. D. 它帮助人们生存。
【考查点】细节事实题
【解题思路】根据题干定位到第一段“The new convergence of biology and economy has been helped by a common methodology—game theory”（生物与经济的新融合得益于一种共同的方法论——博弈论），随后补充其应用场景：经济学家用它“playing a ‘game’ with competing strategies”（以竞争策略“玩游戏”），生物学家用它研究“evolutionary mysteries”（进化谜团）。这表明博弈论是一种“同时应用于经济和进化领域的方法论”，与C选项表述一致，故C选项正确。
【干扰项排除】
A选项“玩游戏的理论”过于表面，博弈论的核心是“用策略分析问题”，而非“玩游戏”，属于曲解原文；
B选项仅提及“进化谜团”，漏了原文中“经济领域”的应用，属于以偏概全；
D选项“它帮助人们生存”错误，原文说进化游戏的“奖励是生存机会”，而非博弈论本身“帮助生存”，属于偷换概念。
第2题:
【选项释义】
The two guilty accomplices mentioned in Para. 2 are ____. 第二段提到的两名共犯是____。
A. part of a drama A. 一部戏剧的一部分
B. used to find a simpler way to explain the game theory B. 用来以更简单的方式解释博弈论
C. to explain how the police punish the crime C. 用来解释警察如何惩罚犯罪
D. to explain how the game theory come into being D. 用来解释博弈论如何形成
【考查点】推理判断题
【解题思路】第二段首句提到“戏剧化版本的博弈如下（A dramatized version of the game runs as follows）”，接着用囚徒困境案例具体说明博弈规则。由此可见，作者通过通俗易懂的案例解释博弈论的核心思想，因此B选项正确。
【干扰项排除】
A选项“一部戏剧的一部分”错误，原文“dramatized version”（戏剧化版本）是“为了便于理解而虚构的场景”，并非真的“戏剧的一部分”，属于曲解原文；
C选项“用来解释警察如何惩罚犯罪”偏离核心，例子的重点是“共犯的策略选择”，而非“警察的惩罚方式”，属于无中生有；
D选项“用来解释博弈论如何形成”，原文未提及博弈论的“形成过程”，该例子仅用于解释博弈论的“具体模型”，属于无中生有。
第3题:
【选项释义】
For the worst situation, what is the total year of the two accomplices’ sentence? 在最坏的情况下，两名共犯的总刑期是多少年？
A. Three years. A. 三年。
B. Five years. B. 五年。
C. Six years. C. 六年。
D. Zero. D. 零年。
【考查点】细节事实题
【解题思路】根据题干定位到第二段。该段明确列出了三种场景的刑期：“If they both confess (or ‘defect’), they will both go to jail for three years. If they both stay silent (or ‘cooperate’), they will both go to jail for a year on a lesser charge that the police can prove. But if one confesses and the other does not, the former will walk free on an agreement, while the cooperator, who stayed silent, will get a five-year sentence.”，即如果两人都坦白（或“背叛”），他们都将入狱三年。如果两人都保持沉默（或“合作”），他们将因警方能证明的较轻罪名而各服刑一年。但如果一人坦白而另一人不坦白，坦白者将根据协议获释，而保持沉默的合作者则将被判五年监禁。由此可知，“最坏情况”是“都坦白”，总刑期六年，故C正确。
【干扰项排除】
A选项“三年”是“每人的刑期”，而非“总刑期”，属于答非所问；
B选项“五年”是“一人坦白、一人沉默”的总刑期，并非最坏情况，属于答非所问；
D选项“零年”是“单独坦白者的刑期”，并非总刑期，属于答非所问。
第4题:
【选项释义】
What are the biologists’ findings for the cooperation strategy? 生物学家关于合作策略的发现是什么？
A. There is no result since the game is in a long series. A. 由于游戏是长期进行的，没有结果。
B. People would like to cooperate. B. 人们愿意合作。
C. People would like to cooperate and what they do next time depends. C. 人们愿意合作，且下次的行为取决于对方上次的做法。
D. People would like not to cooperate. D. 人们不愿意合作。
【考查点】细节事实题
【解题思路】根据“the biologists”定位到第四段。这一段阐述了生物学家的发现：“Under what conditions...would it pay an animal to evolve a strategy based on cooperation...the best strategy is to cooperate on the first trial and then do whatever the other guy did last time”，即“生物学家发现，在长期游戏中，最佳合作策略是‘第一次尝试合作，之后模仿对方上次的行为’”。这与C选项“愿意合作，下次行为取决于对方上次做法”完全一致，故C选项正确。
【干扰项排除】
A选项“由于游戏是长期进行的，没有结果”错误，生物学家明确找到了“tit-for-tat”这一最佳策略，属于反向干扰；
B选项“人们愿意合作”表述不完整，遗漏了“之后模仿对方行为”这一关键条件，属于以偏概全；
D选项“人们不愿意合作”与生物学家发现的“最佳策略基于合作”完全相反，属于反向干扰。
第5题:
【选项释义】
What does tit-for-two-tats mean? “tit-for-two-tats”是什么意思？
A. When one gives tit, the other will give two tats in response. A. 一方先做出某种行为，另一方会以两倍的力度回应。
B. When one gives two tats, the other will give tit in response. B. 一方若以两倍力度做出回应，另一方则会给出相应的反馈。
C. Tit-for-two-tats develops from tit-for-tat. C. “一报还两报（Tit-for-two-tats）”由“以牙还牙（tit-for-tat）”演变而来。
D. When cooperation fails the first time, there will be another chance. D. 当第一次合作失败时，还会有一次机会。
【考查点】语义推断题
【解题思路】根据“tit-for-two-tats”定位到第五段。该段解释了“tit-for-two-tats”的含义：“cooperate even if the other defects once, but not if he defects twice”，即“即使对方背叛一次，仍选择合作；但如果对方背叛两次，则不再合作”。“对方背叛一次（第一次合作失败）仍合作”意味着“第一次合作失败后还有一次机会”，与D选项表述一致，故D选项正确。
【干扰项排除】
A选项“一方先做出某种行为，另一方会以两倍的力度回应”和B选项“一方若以两倍力度做出回应，另一方则会给出相应的反馈”均误解了“tit”和“tats”的含义，原文中“tit”和“tats”并非具体“回应次数”，而是代指“合作”与“背叛”，属于曲解原文；
C选项“一报还两报（Tit-for-two-tats）由以牙还牙（tit-for-tat）演变而来”，原文未提及“发展关系”，属于无中生有。
