Rationalist Explanations for War Author(s): James D. Fearon
Source: International Organization, Vol. 49, No. 3 (Summer, 1995), pp. 379-414
Published by: The MIT Press
Stable URL: http://www.jstor.org/stable/2706903
Accessed: 26-02-2015 23:42 UTC
战争的理性主义解释 作者：James D. Fearon 资料来源资料来源：《国际组织》，第 49 卷，第 3 期（1995 年夏），第 379-414 页。 出版商：麻省理工学院出版社麻省理工学院出版社 稳定 URL: http://www.jstor.org/stable/2706903 访问时间：26-02-2015 23:42 UTC

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The central puzzle about war, and also the main reason we study it, is that wars are costly but nonetheless wars recur. Scholars have attempted to resolve the puzzle with three types of argument. First, one can argue that people (and state leaders in particular) are sometimes or always irrational. They are subject to biases and pathologies that lead them to neglect the costs of war or to misunderstand how their actions will produce it. Second, one can argue that the leaders who order war enjoy its benefits but do not pay the costs, which are suffered by soldiers and citizens. Third, one can argue that even rational leaders who consider the risks and costs of war may end up fighting nonetheless.
战争的核心难题，也是我们研究战争的主要原因，是战争代价高昂，但战争却一再发生。学者们试图通过三种论证来解决这个难题。首先，我们可以认为人（尤其是国家领导人）有时或总是非理性的。他们会受到偏见和病态的影响，从而忽视战争的代价，或误解自己的行为会如何导致战争。其次，我们可以说，下令发动战争的领导人享受了战争带来的好处，但却没有付出代价，而士兵和公民却要为此付出代价。第三，即使是理性的领导人，在考虑到战争的风险和代价后，也可能最终还是会参战。

This article focuses on arguments of the third sort, which I will call rationalist explanations. ${}^1$${}^1$^(1){ }^{1} Rationalist explanations abound in the literature on international conflict, assuming a great variety of specific forms. Moreover, for at least two reasons many scholars have given rationalist explanations a certain pride of place. First, historians and political scientists who have studied the origins of particular wars often have concluded that war can be a rational alternative for leaders who are acting in their states’ interest-they find that the expected benefits of war sometimes outweigh the expected costs, however unfortunate
本文重点讨论第三种论点，我称之为理性主义解释。 ${}^1$${}^1$^(1){ }^{1} 在有关国际冲突的文献中，理性主义解释比比皆是，其具体形式也多种多样。此外，至少出于两个原因，许多学者都赋予理性主义解释以一定的地位。首先，研究过特定战争起源的历史学家和政治学家通常会得出这样的结论：对于那些为了国家利益而行动的领导人来说，战争可能是一种理性的选择--他们发现，战争的预期收益有时会超过预期成本，无论多么不幸。

International Organization 49, 3, Summer 1995, pp. 379-414
国际组织 49，3，1995 年夏，第 379-414 页
© 1995 by The IO Foundation and the Massachusetts Institute of Technology
© 1995 年 IO 基金会和麻省理工学院版权所有
this may be. Second, the dominant paradigm in international relations theory, neorealism, is thought to advance or even to depend on rationalist arguments about the causes of war. Indeed, if no rationalist explanation for war is theoretically or empirically tenable, then neither is neorealism. The causes of war would then lie in the defects of human nature or particular states rather than in the international system, as argued by neorealists. What I refer to here as “rationalist explanations for war” could just as well be called “neorealist explanations.” 2
这可能是。其次，国际关系理论的主流范式--新现实主义--被认为推进甚至依赖于关于战争原因的理性主义论点。事实上，如果理性主义对战争的解释在理论上或经验上都站不住脚，那么新现实主义也是如此。那么，战争的原因就在于人性或特定国家的缺陷，而不是新现实主义者所认为的国际体系。我在这里所说的 "对战争的理性主义解释 "也可以称为 "新现实主义解释"。2

This article attempts to provide a clear statement of what a rationalist explanation for war is and to characterize the full set of rationalist explanations that are both theoretically coherent and empirically plausible. It should be obvious that this theoretical exercise must take place prior to testing rationalist explanations against alternatives-we cannot perform such tests unless we know what a rationalist explanation really is. Arguably, the exercise is also foundational for neorealism. Despite its prominence, neorealist theory lacks a clearly stated and fully conceived explanation for war. As I will argue below, it is not enough to say that under anarchy nothing stops states from using force, or that anarchy forces states to rely on self-help, which engenders mutual suspicion and (through spirals or the security dilemma) armed conflict. Neither do diverse references to miscalculation, deterrence failure because of inadequate forces or incredible threats, preventive and preemptive considerations, or free-riding in alliances amount to theoretically coherent rationalist explanations for war.
本文试图清楚地说明什么是理性主义对战争的解释，并描述一整套理论上连贯、经验上合理的理性主义解释。显而易见，这一理论研究必须先于理性主义解释与其他解释的对比测试--除非我们知道理性主义解释到底是什么，否则我们无法进行这样的测试。可以说，这项工作也是新现实主义的基础。尽管新现实主义理论占据重要地位，但它缺乏对战争的清晰阐述和完整构思的解释。正如我将在下文论述的那样，仅仅说在无政府状态下，没有什么能阻止国家使用武力，或者说无政府状态迫使国家依靠自助，从而导致相互猜疑和（通过螺旋式上升或安全困境）武装冲突，是不够的。关于误判、威慑因力量不足或令人难以置信的威胁而失败、预防性和先发制人的考虑或联盟中的搭便车行为等各种提法，也不能构成理论上连贯的理性主义战争解释。

My main argument is that on close inspection none of the principal rationalist arguments advanced in the literature holds up as an explanation because none addresses or adequately resolves the central puzzle, namely, that war is costly and risky, so rational states should have incentives to locate negotiated settlements that all would prefer to the gamble of war. The common flaw of the standard rationalist arguments is that they fail either to address or to explain adequately what prevents leaders from reaching ex ante (prewar) bargains that would avoid the costs and risks of fighting. A coherent rationalist explanation for war must do more than give reasons why armed conflict might appear an attractive option to a rational leader under some circumstances-it must show why states are unable to locate an alternative outcome that both would prefer to a fight.
我的主要论点是，仔细观察文献中提出的主要理性主义论点，没有一个能站得住脚，因为没有一个论点能解决或充分解决核心问题，即战争成本高、风险大，因此理性国家应该有动力通过谈判达成所有人都愿意接受的解决方案，而不是战争赌博。标准理性主义论点的共同缺陷在于，它们既没有解决也没有充分解释是什么阻碍了领导人达成事前（战前）谈判，从而避免战争的成本和风险。对战争进行连贯的理性主义解释，不仅要说明为什么在某些情况下武装冲突可能对理性的领导人有吸引力，还必须说明为什么国家无法找到一个双方都倾向于战争的替代结果。

To summarize what follows, the article will consider five rationalist arguments accepted as tenable in the literature on the causes of war. Discussed at
概括地说，文章将考虑在有关战争原因的文献中被公认为站得住脚的五个理性主义论点。讨论

length below, these arguments are given the following labels: (1) anarchy; (2) expected benefits greater than expected costs; (3) rational preventive war; (4) rational miscalculation due to lack of information; and (5) rational miscalculation or disagreement about relative power. I argue that the first three arguments simply do not address the question of what prevents state leaders from bargaining to a settlement that would avoid the costs of fighting. The fourth and fifth arguments do address the question, holding that rational leaders may miss a superior negotiated settlement when lack of information leads them to miscalculate relative power or resolve. However, as typically stated, neither argument explains what prevents rational leaders from using diplomacy or other forms of communication to avoid such costly miscalculations.
这些论点被贴上以下标签：(1)无政府状态；(2)预期收益大于预期成本；(3)理性的预防性战争；(4)缺乏信息导致的理性误判；(5)理性误判或对相对权力的分歧。我认为，前三个论点根本没有解决是什么阻碍了国家领导人通过讨价还价达成避免战争成本的解决方案这一问题。第四和第五个论点确实解决了这个问题，它们认为，当缺乏信息导致理性的领导者误判相对实力或决心时，他们可能会错过一个更好的谈判解决方案。然而，正如通常所说的那样，这两个论点都没有解释是什么阻碍了理性的领导人利用外交或其他形式的沟通来避免这种代价高昂的误判。

If these standard arguments do not resolve the puzzle on rationalist terms, what does? I propose that there are three defensible answers, which take the form of general mechanisms, or causal logics, that operate in a variety of more specific international contexts. ${}^3$${}^3$^(3){ }^{3} In the first mechanism, rational leaders may be unable to locate a mutually preferable negotiated settlement due to private information about relative capabilities or resolve and incentives to misrepresent such information. Leaders know things about their military capabilities and willingness to fight that other states do not know, and in bargaining situations they can have incentives to misrepresent such private information in order to gain a better deal. I show that given these incentives, communication may not allow rational leaders to clarify relative power or resolve without generating a real risk of war. This is not simply a matter of miscalculation due to poor information but rather of specific strategic dynamics that result from the combination of asymmetric information and incentives to dissemble.
如果这些标准论据不能从理性主义角度解决这一难题，那么什么才能解决呢？我提出了三种站得住脚的答案，它们以一般机制或因果逻辑的形式出现，在各种更为具体的国际环境中发挥作用。 ${}^3$${}^3$^(3){ }^{3} 在第一种机制中，理性的领导人可能会因为有关相对能力或决心的私人信息以及歪曲这些信息的动机而无法找到双方都喜欢的谈判解决方案。领导人对自己的军事能力和战斗意愿的了解是其他国家所不知道的，在讨价还价的情况下，他们可能有动机歪曲这些私人信息，以获得更好的交易。我的研究表明，在这些动机的驱使下，理性的领导人可能无法通过沟通来澄清相对实力或决心，而又不会引发真正的战争风险。这不仅仅是信息不全导致的误判问题，而是信息不对称和动机失实共同作用下的特定战略动态问题。

Second, rationally led states may be unable to arrange a settlement that both would prefer to war due to commitment problems, situations in which mutually preferable bargains are unattainable because one or more states would have an incentive to renege on the terms. While anarchy (understood as the absence of an authority capable of policing agreements) is routinely cited as a cause of war in the literature, it is difficult to find explanations for exactly why the inability to make commitments should imply that war will sometimes occur. That is, what are the specific, empirically identifiable mechanisms by which the inability to commit makes it impossible for states to strike deals that would avoid the costs of war? I identify three such specific mechanisms, arguing in particular that preventive war between rational states stems from a commitment problem rather than from differential power growth per se.
其次，由于承诺问题，理性主导的国家可能无法达成双方都倾向于战争的解决方案，在这种情况下，双方都倾向于的交易是无法达成的，因为一个或多个国家有动机违背条款。虽然无政府状态（被理解为缺乏能够监督协议的权威机构）在文献中经常被引述为战争的原因，但很难找到确切的解释来说明为什么无法做出承诺意味着战争有时会发生。也就是说，有哪些具体的、经验上可识别的机制，使得无法做出承诺的国家无法达成避免战争代价的协议？我提出了三个这样的具体机制，并特别指出，理性国家之间的预防性战争源于承诺问题，而非实力增长差异本身。
The third sort of rationalist explanation I find less compelling than the first two, although it is logically tenable. States might be unable to locate a peaceful
第三种理性主义解释虽然在逻辑上站得住脚，但我认为不如前两种解释更有说服力。各国可能无法找到一个和平

settlement both prefer due to issue indivisibilities. Perhaps some issues, by their very natures, simply will not admit compromise. Though neither example is wholly convincing, issues that might exhibit indivisibility include abortion in domestic politics and the problem of which prince sits on the throne of, say, Spain, in eighteenth- or nineteenth-century international politics. Issue indivisibility could in principle make war rational for the obvious reason that if the issue allows only a finite number of resolutions, it might be that none falls within the range that both prefer to fighting. However, the issues over which states bargain typically are complex and multidimensional; side-payments or linkages with other issues typically are possible; and in principle states could alternate or randomize among a fixed number of possible solutions to a dispute. War-prone international issues may often be effectively indivisible, but the cause of this indivisibility lies in domestic political and other mechanisms rather than in the nature of the issues themselves.
由于问题的不可分割性，两者都倾向于和解。也许有些问题，就其本质而言，根本无法达成妥协。虽然这两个例子都不完全令人信服，但可能表现出不可分割性的问题包括国内政治中的堕胎问题，以及十八或十九世纪国际政治中的西班牙王位归属问题。问题的不可分割性原则上可以使战争变得合理，原因显而易见，如果问题只允许有限数量的解决方案，那么可能没有一个解决方案是在双方都倾向于战斗的范围内。然而，各国讨价还价的问题通常是复杂的、多层面的；附带利益或与其他问题的联系通常是可能的；原则上，各国可以在解决争端的固定数量的可能方案中交替或随机选择。容易引发战争的国际问题往往实际上是不可分割的，但造成这种不可分割性的原因在于国内政治和其他机制，而不是问题本身的性质。

In the first section of the article I discuss the puzzle posed by the fact that war is costly. Using a simple formalization of the bargaining problem faced by states in conflict, I show that under very broad conditions bargains will exist that genuinely rational states would prefer to a risky and costly fight. The second section argues that rational miscalculations of relative power and resolve must be due to private information and then considers how war may result from the combination of private information and incentives to misrepresent that information in bargaining. In the third section, I discuss commitment problems as the second class of defensible rationalist explanations for war. Throughout, I specify theoretical arguments with simple game-theoretic representations and assess plausibility with historical examples.
在文章的第一部分，我讨论了战争代价高昂这一事实所带来的困惑。通过对冲突中的国家所面临的讨价还价问题进行简单的形式化，我证明了在非常宽泛的条件下，真正理性的国家会选择讨价还价，而不是冒险且代价高昂的战争。第二部分论证了对相对实力和决心的理性误判一定是由私人信息造成的，然后探讨了私人信息和在讨价还价中歪曲信息的动机如何共同导致战争。在第三节中，我将讨论承诺问题，将其作为对战争的第二类站得住脚的理性主义解释。在整个过程中，我用简单的博弈论表述来具体说明理论论点，并用历史实例来评估其合理性。

Before beginning, I should make it clear that I am not presenting either commitment problems or private information and incentives to misrepresent as wholly novel explanations for war that are proposed here for the first time. The literature on the causes of war is massive, and these ideas, mixed with myriad others, can be found in it in various guises. The main theoretical task facing students of war is not to add to the already long list of arguments and conjectures but instead to take apart and reassemble these diverse arguments into a coherent theory fit for guiding empirical research. Toward this end, I am arguing that when one looks carefully at the problem of explaining how war could occur between genuinely rational, unitary states, one finds that there are really only two ways to do it. The diverse rationalist or neorealist explanations commonly found in the literature fail for two reasons. First, many do not even address the relevant question-what prevents states from locating a bargain both sides would prefer to a fight? They do not address the question because it is widely but incorrectly assumed that rational states can face a situation of deadlock, wherein no agreements exist that both sides would prefer to a war. ${}^4$${}^4$^(4){ }^{4}
在开始之前，我需要说明的是，我既没有提出承诺问题，也没有提出私人信息和动机失实问题，这些都是我首次提出的关于战争的全新解释。关于战争原因的文献浩如烟海，这些观点以及无数其他观点以各种面目出现在文献中。研究战争的学生所面临的主要理论任务不是在已经很长的论点和猜想清单上再添加新的论点和猜想，而是将这些不同的论点拆分开来，重新组合成一个适合指导实证研究的连贯理论。为此，我认为，当我们仔细研究如何解释战争如何在真正理性的单一国家之间发生的问题时，我们会发现实际上只有两种方法可以做到这一点。文献中常见的各种理性主义或新现实主义解释之所以失败，原因有二。首先，许多解释甚至都没有涉及相关问题--是什么阻碍了国家找到一个双方都倾向于的讨价还价方案，而不是一场争斗？他们之所以没有回答这个问题，是因为人们普遍错误地认为，理性的国家可能会面临僵局，即不存在双方都希望达成的协议，而不是战争。 ${}^4$${}^4$^(4){ }^{4}

Second, the rationalist arguments that do address the question-such as (4) and (5) above-do not go far enough in answering it. When fully developed, they prove to be one of the two major mechanisms developed here, namely, either a commitment problem or a problem arising from private information and incentives to misrepresent. These two mechanisms, I will argue, provide the foundations for a rationalist or neorealist theory of war.
其次，理性主义的论证确实涉及到了这一问题--例如上文（4）和（5）--但在回答这一问题时还不够深入。当这些论证得到充分发展时，它们被证明是本文提出的两大机制之一，即要么是承诺问题，要么是由私人信息和虚假陈述动机引起的问题。我认为，这两种机制为理性主义或新现实主义战争理论提供了基础。

Most historians and political scientists who study war dismiss as naive the view that all wars must be unwanted because they entail destruction and suffering. Instead, most agree that while a few wars may have been unwanted by the leaders who brought them about-World War I is sometimes given as an example-many or perhaps most wars were simply wanted. The leaders involved viewed war as a costly but worthwhile gamble. ${}^5$${}^5$^(5){ }^{5}
大多数研究战争的历史学家和政治学家都认为，所有战争都是不受欢迎的，因为它们会带来破坏和痛苦，这种观点太天真了。相反，大多数人都认为，虽然少数战争可能是发动战争的领导人所不希望发生的--第一次世界大战有时就是一个例子--但许多战争，甚至大多数战争都是想要发生的。有关领导人认为战争是一场代价高昂但值得一赌的赌博。 ${}^5$${}^5$^(5){ }^{5}

Moreover, many scholars believe that wanted wars are easily explained from a rationalist perspective. Wanted wars are thought to be Pareto-efficient-they occur when no negotiated settlements exist that both sides would prefer to the gamble of military conflict. Conventional wisdom holds that while this situation may be tragic, it is entirely possible between states led by rational leaders who consider the costs and risks of fighting. Unwanted wars, which take place despite the existence of settlements both sides preferred to conflict, are thought to pose more of a puzzle, but one that is resolvable and also fairly rare.
此外，许多学者认为，从理性主义的角度来看，通缉战争很容易解释。被通缉的战争被认为是帕累托效率的战争--当双方都不愿意通过谈判解决问题，而不愿意冒军事冲突的风险时，战争就会发生。传统智慧认为，虽然这种情况可能是悲剧性的，但在由理性领导人领导的国家之间是完全可能发生的，因为他们会考虑战斗的成本和风险。不希望发生的战争，即尽管存在双方都希望的解决办法，但却发生了，这被认为是一个更大的难题，但却是可以解决的，而且也相当罕见。

The conventional distinction between wanted and unwanted wars misunderstands the puzzle posed by war. The reason is that the standard conception does not distinguish between two types of efficiency-ex ante and ex post. As long as both sides suffer some costs for fighting, then war is always inefficient $ex$$ex$exe x post-both sides would have been better off if they could have achieved the same final resolution without suffering the costs (or by paying lower costs). This is true even if the costs of fighting are small, or if one or both sides viewed the potential benefits as greater than the costs, since there are still costs. Unless states enjoy the activity of fighting for its own sake, as a consumption good, then war is inefficient ex post.
传统上对想要的战争和不想要的战争的区分误解了战争带来的难题。原因在于，标准概念没有区分事前和事后两种效率。只要交战双方都要付出一定的代价，那么战争在事后总是无效率的 $ex$$ex$exe x --如果双方都能在不付出代价（或付出较低代价）的情况下达成同样的最终解决方案，那么双方都会过得更好。即使战争的成本很小，或者一方或双方认为潜在的利益大于成本，情况也是如此，因为仍然存在成本。除非国家喜欢为战斗而战斗，将其作为一种消费品，否则战争事后就是无效率的。

From a rationalist perspective, the central puzzle about war is precisely this ex post inefficiency. Before fighting, both sides know that war will entail some costs, and even if they expect offsetting benefits they still have an incentive to avoid the costs. The central question, then, is what prevents states in a dispute
从理性主义的角度来看，战争的核心难题正是这种事后的无效率。在开战之前，双方都知道战争会带来一些代价，即使他们预期会有抵消的利益，他们仍然有动机避免代价。因此，核心问题是，是什么阻止了争端中的国家

from reaching an ex ante agreement that avoids the costs they know will be paid ex post if they go to war? Giving a rationalist explanation for war amounts to answering this question.
达成一项事前协议，以避免他们知道一旦开战就会付出事后代价？对战争做出理性主义的解释就等于回答了这个问题。

Three of the most common and widely employed rationalist arguments in the literature do not directly address or answer the question. These are arguments from anarchy, preventive war, and positive expected utility.
文献中最常见和最广泛使用的三个理性主义论证并没有直接涉及或回答这个问题。它们是无政府状态论证、预防性战争论证和正期望效用论证。

Since Kenneth Waltz’s influential Man, the State, and War, the anarchical nature of the international realm is routinely cited as a root cause of or explanation for the recurrence of war. Waltz argued that under anarchy, without a supranational authority to make and enforce law, “war occurs because there is nothing to prevent it. . . . Among states as among men there is no automatic adjustment of interests. In the absence of a supreme authority there is then the constant possibility that conflicts will be settled by force.” ${}^6$${}^6$^(6){ }^{6}
自肯尼思-华尔兹（Kenneth Waltz）发表了影响深远的《人、国家与战争》（Man, the State, and War）一书以来，国际领域的无政府主义性质经常被作为战争频发的根本原因或解释。华尔兹认为，在无政府状态下，没有超国家的权威来制定和执行法律，"战争之所以发生，是因为没有任何东西可以阻止它。. . .......国家之间就像人与人之间一样，利益不会自动调整。在没有最高权威的情况下，冲突就始终有可能通过武力来解决"。 ${}^6$${}^6$^(6){ }^{6}
The argument focuses our attention on a fundamental difference between domestic and international politics. Within a well-ordered state, organized violence as a strategy is ruled out-or at least made very dangerous-by the potential reprisals of a central government. In international relations, by contrast, no agency exists that can credibly threaten reprisal for the use of force to settle disputes. ${}^7$${}^7$^(7){ }^{7} The claim is that without such a credible threat, war will sometimes appear the best option for states that have conflicting interests.
这一论点将我们的注意力集中在国内政治与国际政治的根本区别上。在一个秩序井然的国家中，有组织的暴力作为一种策略是被排除在外的，或者至少会因为中央政府的潜在报复而变得非常危险。与此相反，在国际关系中，没有任何机构可以令人信服地威胁要对使用武力解决争端的行为进行报复。 ${}^7$${}^7$^(7){ }^{7} 这种说法认为，如果没有这种可信的威胁，战争有时就会成为利益冲突国的最佳选择。

While I do not doubt that the condition of anarchy accounts for major differences between domestic and international politics, and that anarchy encourages both fear of and opportunities for military conflict, the standard framing of the argument is not enough to explain why wars occur and recur. Under anarchy, nothing stops states from using force if they wish. But if using force is a costly option regardless of the outcome, then why is it ever employed? How exactly does the lack of a central authority prevent states from negotiating agreements both sides would prefer to fighting? As it is typically stated, the argument that anarchy provides a rationalist explanation for war does not address this question and so does not solve the problem posed by war’s ex post inefficiency.
虽然我并不怀疑无政府状态造成了国内政治和国际政治之间的重大差异，而且无政府状态既助长了对军事冲突的恐惧，也助长了军事冲突的机会，但这一论点的标准框架并不足以解释战争为什么会发生和反复发生。在无政府状态下，如果国家愿意，没有什么能阻止它们使用武力。但是，如果无论结果如何，使用武力都是代价高昂的选择，那么为什么还会使用武力呢？缺乏中央权威究竟是如何阻止国家通过谈判达成双方都希望达成的协议，而不是通过战争呢？正如通常所说的那样，无政府状态为战争提供了理性主义的解释这一论点并没有解决这个问题，因此也没有解决战争的事后无效率问题。

Neither, it should be added, do related arguments invoking the security dilemma, the fact that under anarchy one state’s efforts to make itself more secure can have the undesired but unavoidable effect of making another state
应该补充的是，援引安全困境的相关论点也是如此，即在无政府状态下，一个国家为使自身更加安全而做出的努力可能会产生不希望但却不可避免的结果，使另一个国家变得更加安全。
6. The quotation is drawn from Kenneth Waltz, Man, the State, and War: A Theoretical Analysis (New York: Columbia University Press, 1959), p. 188.
6.引文摘自肯尼斯-华尔兹，《人、国家与战争：理论分析》（纽约：哥伦比亚大学出版社，1959 年），第 188 页。
7. For a careful analysis and critique of this standard argument on the difference between the international and domestic arenas, see R. Harrison Wagner, “The Causes of Peace,” in Roy A. Licklider, ed., Stopping the Killing: How Civil Wars End (New York: New York University Press, 1993), pp. 235-68 and especially pp. 251-57.
关于对国际舞台和国内舞台之间差异的标准论点的仔细分析和批评，见 R. Harrison Wagner，"The Causes of Peace"，载于 Roy A. Licklider 编辑的《停止杀戮：内战如何结束》（纽约：纽约大学出版社，1993 年），第 235-68 页，特别是第 25-57 页：内战如何结束》（纽约：纽约大学出版社，1993 年），第 235-68 页，尤其是第 251-57 页。
less secure. ${}^8$${}^8$^(8){ }^{8} By itself this fact says nothing about the availability or feasibility of peaceful bargains that would avoid the costs of war. More elaborate arguments are required, and those that are typically given do not envision bargaining and do not address the puzzle of costs. Consider, for instance, a spiral scenario in which an insecure state increases its arms, rendering another so insecure that it decides to attack. If the first state anticipated the reaction producing war, then by itself this is a deadlock argument; I argue against these below. If the first state did not anticipate war and did not want it, then the problem would seem to be miscalculation rather than anarchy, and we need to know why signaling and bargaining could not have solved it. As Robert Jervis has argued, anarchy and the security dilemma may well foster arms races and territorial competition. ${}^9$${}^9$^(9){ }^{9} But with the exception of occasional references to the preemptive war problem, the standard security dilemma arguments do not explicitly address the question of why the inability to make commitments should necessarily make for war between rational states. ${}^{10}$${}^{10}$^(10){ }^{10}
更不安全。 ${}^8$${}^8$^(8){ }^{8} 这一事实本身并没有说明可以避免战争成本的和平谈判是否存在或可行。我们需要更详尽的论证，而那些通常给出的论证并没有设想讨价还价，也没有解决成本的难题。例如，考虑一个螺旋式上升的情景：一个不安全的国家增加军备，使另一个国家变得如此不安全，以至于决定发动攻击。如果第一个国家预料到了会产生战争的反应，那么这本身就是一个僵局论证；我将在下文反驳这些论证。如果第一个国家没有预料到战争，也不希望战争发生，那么问题似乎就不是无政府状态，而是误判，我们需要知道为什么信号传递和讨价还价不能解决这个问题。正如罗伯特-杰维斯（Robert Jervis）所言，无政府状态和安全困境很可能会助长军备竞赛和领土竞争。 ${}^9$${}^9$^(9){ }^{9} 但是，除了偶尔提到先发制人的战争问题之外，标准的安全困境论证并没有明确解决为什么无法做出承诺必然会导致理性国家之间发生战争的问题。 ${}^{10}$${}^{10}$^(10){ }^{10}

Below I will argue that anarchy is indeed implicated as a cause of specific sorts of military conflict (e.g., preventive and preemptive war and in some cases war over strategic territory). In contrast to the standard arguments, however, showing how anarchy figures in a coherent rationalist explanation entails describing the specific mechanism by which states’ inability to write enforceable contracts makes peaceful bargains both sides would prefer unattainable.
下面，我将论证无政府状态确实是特定军事冲突（如预防性战争和先发制人的战争，以及在某些情况下争夺战略领土的战争）的原因之一。然而，与标准论点不同的是，要说明无政府状态如何体现在一个连贯的理性主义解释中，就必须描述国家无法书写可执行契约的具体机制，从而使双方都希望达成的和平协议无法实现。

It frequently is argued that if a declining power expects it might be attacked by a rising power in the future, then a preventive war in the present may be rational. Typically, however, preventive war arguments do not consider whether the rising and declining powers could construct a bargain, perhaps across time, that would leave both sides better off than a costly and risky preventive war would. ${}^{11}$${}^{11}$^(11){ }^{11} The incentives for such a deal surely exist. The rising state should not want to be attacked while it is relatively weak, so what stops it from offering concessions in the present and the future that would make the declining state prefer not to attack? Also, if war is inefficient and bargains both sides prefer to a fight will exist, why should the declining power rationally fear being attacked in the future? The standard argument supposes that an
经常有人认为，如果衰落的大国预计未来可能受到崛起大国的攻击，那么在当前发动预防性战争可能是合理的。然而，预防性战争的论点通常不会考虑崛起的大国和衰落的大国是否可以达成一项交易，也许是跨时间的交易，从而使双方都能获得比代价高昂、风险巨大的预防性战争更好的结果。 ${}^{11}$${}^{11}$^(11){ }^{11} 这种交易的动机肯定是存在的。崛起的国家应该不希望在自己相对弱小的时候受到攻击，那么有什么能阻止它在现在和未来做出让步，让衰落的国家宁愿不进攻呢？另外，如果战争是低效的，而且双方都倾向于讨价还价，那么为什么衰落国在理性上会害怕在未来受到攻击呢？标准论证假设

anticipated shift in the balance of power can by itself be enough to make war rational, but this is not so.
力量对比的预期变化本身就足以使战争变得合理，但事实并非如此。

Perhaps the most common informal rationalist explanation found in the literature is that war may occur when two states each estimate that the expected benefits of fighting outweigh the expected costs. As Bruce Bueno de Mesquita argued in an influential formalization of this claim, war can be rational if both sides have positive expected utility for fighting; that is, if the expected utility of war (expected benefits less costs) is greater than the expected utility of remaining at peace. ${}^{12}$${}^{12}$^(12){ }^{12}
文献中最常见的非正式理性主义解释或许是，当两个国家都认为战争的预期收益大于预期成本时，战争就可能发生。正如布鲁斯-布埃诺-德-梅斯基塔（Bruce Bueno de Mesquita）在对这一主张进行有影响力的形式化时所论证的，如果双方对战争都有正的预期效用，战争就可能是理性的；也就是说，如果战争的预期效用（预期收益减去成本）大于保持和平的预期效用，战争就可能是理性的。 ${}^{12}$${}^{12}$^(12){ }^{12}

Informal versions of the expected utility argument typically fail to address the question of how or under what conditions it can be possible for two states both to prefer the costly gamble of war to any negotiated settlement. Formal versions have tended to avoid the question by making various restrictive and sometimes nonrationalist assumptions. To support these claims, I need to be more precise about the expected utility argument.
预期效用论证的非正式版本通常无法解决这样一个问题：两个国家如何或在什么条件下都宁愿选择代价高昂的战争而不是任何谈判解决。正式版本往往通过各种限制性的、有时是非理性主义的假设来回避这个问题。为了支持这些主张，我需要更精确地说明预期效用论证。

This section considers the question of whether and when two rationally led states could both prefer war to any negotiated settlement.
本节探讨的问题是，两个理性主导的国家是否以及何时都会选择战争而非谈判解决。
Consider two states, A and B, who have preferences over a set of issues represented by the interval $X=[0,1]$$X=[0,1]$X=[0,1]X=[0,1]. State A prefers issue resolutions closer to 1 , while B prefers outcomes closer to 0 . Let the states’ utilities for the outcome $x\in X$$x\in X$x in Xx \in X be $u_A(x)$$u_A(x)$u_(A)(x)u_{A}(x) and $u_B(1-x)$$u_B(1-x)$u_(B)(1-x)u_{B}(1-x), and assume for now that $u_A(\cdot )$$u_A(\cdot )$u_(A)(*)u_{A}(\cdot) and $u_B(\cdot )$$u_B(\cdot )$u_(B)(*)u_{B}(\cdot) are continuous, increasing, and weakly concave (that is, risk-neutral or risk-averse). Without losing any generality, we can set $u_i(1)=1$$u_i(1)=1$u_(i)(1)=1u_{i}(1)=1 and $u_i(0)=0$$u_i(0)=0$u_(i)(0)=0u_{i}(0)=0 for both states $(i=A,B)$$(i=A,B)$(i=A,B)(i=A, B). For concreteness we might think of $x$$x$xx as representing the proportion of all territory between A and B that is controlled by A .
考虑两个国家 A 和 B，它们对区间 $X=[0,1]$$X=[0,1]$X=[0,1]X=[0,1] 所代表的一组问题具有偏好。A 国偏好接近 1 的问题决议，而 B 国偏好接近 0 的结果。假设各州对结果 $x\in X$$x\in X$x in Xx \in X 的效用分别为 $u_A(x)$$u_A(x)$u_(A)(x)u_{A}(x) 和 $u_B(1-x)$$u_B(1-x)$u_(B)(1-x)u_{B}(1-x) ，并暂时假设 $u_A(\cdot )$$u_A(\cdot )$u_(A)(*)u_{A}(\cdot) 和 $u_B(\cdot )$$u_B(\cdot )$u_(B)(*)u_{B}(\cdot) 是连续、递增和弱凹（即风险中性或风险规避）的。在不失一般性的前提下，我们可以为 $(i=A,B)$$(i=A,B)$(i=A,B)(i=A, B) 两种状态设置 $u_i(1)=1$$u_i(1)=1$u_(i)(1)=1u_{i}(1)=1 和 $u_i(0)=0$$u_i(0)=0$u_(i)(0)=0u_{i}(0)=0 。具体来说，我们可以把 $x$$x$xx 视为 A 和 B 之间由 A 控制的所有领土的比例。
In order to say whether the set $X$$X$XX contains negotiated settlements that both sides would prefer to conflict, it must be possible to say how the states evaluate the military option versus those outcomes. Almost all analysts of war have
要想知道 $X$$X$XX 集合中是否包含双方都希望通过谈判达成的解决方案，就必须知道各国是如何评估军事选择与这些结果之间的关系的。几乎所有的战争分析家都

FIGURE 1. The bargaining range
图 1.谈判范围
stressed that war is a gamble whose outcome may be determined by random or otherwise unforeseeable events. ${}^{13}$${}^{13}$^(13){ }^{13} As Bueno de Mesquita argued, this makes expected utility a natural candidate. ${}^{14}$${}^{14}$^(14){ }^{14} Suppose that if the states fight a war, state A prevails with probability $p\in [0,1]$$p\in [0,1]$p in[0,1]p \in[0,1], and that the winner gets to choose its favorite outcome in the issue space. It follows that A’s expected utility for war is $p{u}_A(1)+(1-p)u_A(0)-c_A$$p{u}_A(1)+(1-p)u_A(0)-c_A$pu_(A)(1)+(1-p)u_(A)(0)-c_(A)p u_{A}(1)+(1-p) u_{A}(0)-c_{A}, or $p-c_A$$p-c_A$p-c_(A)p-c_{A}, where $c_A$$c_A$c_(A)c_{A} is state A’s utility for the costs of a war. Similarly, state B’s expected utility for war will be $1-p-c_B$$1-p-c_B$1-p-c_(B)1-p-c_{B}. Since we are considering rationalist theories for war, we assume that $c_A$$c_A$c_(A)c_{A} and $c_B$$c_B$c_(B)c_{B} are both positive. War is thus represented as a costly lottery. (Note that in this formulation the terms $c_A$$c_A$c_(A)c_{A} and $c_B$$c_B$c_(B)c_{B} capture not only the states’ values for the costs of war but also the value they place on winning or losing on the issues at stake. That is, $c_A$$c_A$c_(A)c_{A} reflects state A’s costs for war relative to any possible benefits. For example, if the two states see little to gain from winning a war against each other, then $c_A$$c_A$c_(A)c_{A} and $c_B$$c_B$c_(B)c_{B} would be large even if neither side expected to suffer much damage in a war.)
他强调，战争是一场赌博，其结果可能由随机事件或其他不可预见的事件决定。 ${}^{13}$${}^{13}$^(13){ }^{13} 正如布埃诺德梅斯基塔所言，这使得预期效用成为一个自然的候选方案。 ${}^{14}$${}^{14}$^(14){ }^{14} 假设如果各国开战，A国获胜的概率为 $p\in [0,1]$$p\in [0,1]$p in[0,1]p \in[0,1] ，胜者可以在问题空间中选择自己最喜欢的结果。因此，A 国对战争的预期效用为 $p{u}_A(1)+(1-p)u_A(0)-c_A$$p{u}_A(1)+(1-p)u_A(0)-c_A$pu_(A)(1)+(1-p)u_(A)(0)-c_(A)p u_{A}(1)+(1-p) u_{A}(0)-c_{A} ，或 $p-c_A$$p-c_A$p-c_(A)p-c_{A} ，其中 $c_A$$c_A$c_(A)c_{A} 是 A 国对战争成本的效用。同样，B 国对战争的预期效用将是 $1-p-c_B$$1-p-c_B$1-p-c_(B)1-p-c_{B} 。由于我们考虑的是理性主义的战争理论，我们假定 $c_A$$c_A$c_(A)c_{A} 和 $c_B$$c_B$c_(B)c_{B} 都是正数。因此，战争被表述为代价高昂的抽签。(请注意，在这一表述中， $c_A$$c_A$c_(A)c_{A} 和 $c_B$$c_B$c_(B)c_{B} 不仅反映了国家对战争成本的估价，也反映了国家对战争输赢的估价。也就是说， $c_A$$c_A$c_(A)c_{A} 反映的是A国的战争成本相对于任何可能的利益。例如，如果两个国家都认为赢得战争对彼此没有什么好处，那么即使双方都不希望在战争中遭受太大损失， $c_A$$c_A$c_(A)c_{A} 和 $c_B$$c_B$c_(B)c_{B} 也会很大。）

We can now answer the question posed above. The following result is easily demonstrated: given the assumptions stated in the last two paragraphs, there always exists a set of negotiated settlements that both sides prefer to fighting. ${}^{15}$${}^{15}$^(15){ }^{15} Formally, there exists a subset of $X$$X$XX such that for each outcome $x$$x$xx in this set, $u_A(x)>p-c_A$$u_A(x)>p-c_A$u_(A)(x) > p-c_(A)u_{A}(x)>p-c_{A} and $u_B(1-x)>1-p-c_B$$u_B(1-x)>1-p-c_B$u_(B)(1-x) > 1-p-c_(B)u_{B}(1-x)>1-p-c_{B}. For example, in the risk-neutral case where $u_A(x)=x$$u_A(x)=x$u_(A)(x)=xu_{A}(x)=x and $u_B(1-x)=1-x$$u_B(1-x)=1-x$u_(B)(1-x)=1-xu_{B}(1-x)=1-x, both states will strictly prefer any peaceful agreement in the interval $(p-c_A,p+c_B)$$\left(p-c_A,p+c_B\right)$(p-c_(A),p+c_(B))\left(p-c_{A}, p+c_{B}\right) to fighting. This interval represents the bargaining range, with $p-c_A$$p-c_A$p-c_(A)p-c_{A} and $p+c_B$$p+c_B$p+c_(B)p+c_{B} as the reservation levels that delimit it. A risk-neutral case is depicted in Figure 1.
现在我们可以回答上文提出的问题了。下面的结果很容易证明：在上两段所述假设的前提下，总是存在一组双方都喜欢的谈判解决方案，而不是战斗。 ${}^{15}$${}^{15}$^(15){ }^{15} 形式上，存在一个 $X$$X$XX 子集，使得这个集合中的每个结果 $x$$x$xx 都是 $u_A(x)>p-c_A$$u_A(x)>p-c_A$u_(A)(x) > p-c_(A)u_{A}(x)>p-c_{A} 和 $u_B(1-x)>1-p-c_B$$u_B(1-x)>1-p-c_B$u_(B)(1-x) > 1-p-c_(B)u_{B}(1-x)>1-p-c_{B} 。例如，在 $u_A(x)=x$$u_A(x)=x$u_(A)(x)=xu_{A}(x)=x 和 $u_B(1-x)=1-x$$u_B(1-x)=1-x$u_(B)(1-x)=1-xu_{B}(1-x)=1-x 的风险中性情况下，两国都会严格倾向于 $(p-c_A,p+c_B)$$\left(p-c_A,p+c_B\right)$(p-c_(A),p+c_(B))\left(p-c_{A}, p+c_{B}\right) 区间内的任何和平协议，而不是战斗。这个区间代表讨价还价的范围， $p-c_A$$p-c_A$p-c_(A)p-c_{A} 和 $p+c_B$$p+c_B$p+c_(B)p+c_{B} 是划分这个区间的保留水平。风险中性的情况如图 1 所示。

This simple but important result is worth belaboring with some intuition. Suppose that two people (or states) are bargaining over the division of $100-if they can agree on a split they can keep what they agree to. However, in contrast
这个简单而重要的结果值得用一些直觉来加以阐述。假设有两个人（或两个国家）正在就 100 美元的分割问题讨价还价--如果他们能就分割问题达成一致，他们就能保住他们同意的东西。然而，与此相反
13. See, for classic examples, Thucydides, The Peloponnesian War (New York: Modern Library, 1951), pp. 45 and 48; and Carl von Clausewitz, On War (Princeton, N.J.: Princeton University Press, 1984), p. 85.
经典案例见修昔底德，《伯罗奔尼撒战争》（纽约：现代图书馆，1951 年），第 45 和 48 页；卡尔-冯-克劳塞维茨，《战争论》（新泽西州普林斯顿：普林斯顿大学出版社，1984 年），第 85 页。
14. Bueno de Mesquita, The War Trap.
14.Bueno de Mesquita，《战争陷阱》。
15. A proof is given in the Appendix.
15.证明见附录。
to the usual economic scenarios, in this international relations example the players also have an outside option. ${}^{16}$${}^{16}$^(16){ }^{16} For a price of $\mathrm{\$}20$$\mathrm{\$}20$$20\$ 20, they can go to war, in which case each player has a 50 -percent chance of winning the whole $\mathrm{\$}100$$\mathrm{\$}100$$100\$ 100. This implies that the expected value of the war option is $\mathrm{\$}30(0.5\cdot 100+0.5\cdot 0-20)$$\mathrm{\$}30(0.5\cdot 100+0.5\cdot 0-20)$$30(0.5*100+0.5*0-20)\$ 30(0.5 \cdot 100+0.5 \cdot 0-20) for each side, so that if the players are risk-neutral, then neither should be willing to accept less than $\mathrm{\$}30$$\mathrm{\$}30$$30\$ 30 in the bargaining. But notice that there is still a range of peaceful, bargained outcomes from $(\mathrm{\$}31,\mathrm{\$}69)$$(\mathrm{\$}31,\mathrm{\$}69)$($31,$69)(\$ 31, \$ 69) to $(\mathrm{\$}69,\mathrm{\$}31)$$(\mathrm{\$}69,\mathrm{\$}31)$($69,$31)(\$ 69, \$ 31) that make both sides strictly better off than the war option. Risk aversion will tend to increase the range yet further; indeed, even if the leaders pay no costs for war, a set of agreements both sides prefer to a fight will still exist provided both are risk-averse over the issues. In effect, the costs and risks of fighting open up a “wedge” of bargained solutions that risk-neutral or risk-averse states will prefer to the gamble of conflict. The existence of this ex ante bargaining range derives from the fact that war is inefficient ex post.
与通常的经济情景不同，在这个国际关系示例中，玩家还有一个外部选择。 ${}^{16}$${}^{16}$^(16){ }^{16} 只要付出 $\mathrm{\$}20$$\mathrm{\$}20$$20\$ 20 的代价，他们就可以开战，在这种情况下，每一方都有 50%的机会赢得整个 $\mathrm{\$}100$$\mathrm{\$}100$$100\$ 100 。这意味着战争选项的期望值对每一方来说都是 $\mathrm{\$}30(0.5\cdot 100+0.5\cdot 0-20)$$\mathrm{\$}30(0.5\cdot 100+0.5\cdot 0-20)$$30(0.5*100+0.5*0-20)\$ 30(0.5 \cdot 100+0.5 \cdot 0-20) ，因此，如果博弈者是风险中性的，那么在讨价还价中，双方都不应该愿意接受低于 $\mathrm{\$}30$$\mathrm{\$}30$$30\$ 30 的价格。但是请注意，从 $(\mathrm{\$}31,\mathrm{\$}69)$$(\mathrm{\$}31,\mathrm{\$}69)$($31,$69)(\$ 31, \$ 69) 到 $(\mathrm{\$}69,\mathrm{\$}31)$$(\mathrm{\$}69,\mathrm{\$}31)$($69,$31)(\$ 69, \$ 31) ，仍然存在一系列和平的、讨价还价的结果，这些结果使双方的境况都严格优于战争选项。风险规避倾向于进一步扩大这个范围；事实上，即使领导人不为战争付出任何代价，只要双方都在这些问题上规避风险，那么双方都更喜欢的协议集合仍然存在。实际上，战争的成本和风险为讨价还价的解决方案开辟了一个 "楔子"，风险中性或风险规避型国家更愿意选择这种解决方案，而不是冒险冲突。这种事前讨价还价范围的存在源于战争事后效率低下这一事实。

Three substantive assumptions are needed for the result, none of which seems particularly strong. First, the states know that there is some true probability $p$$p$pp that one state would win in a military contest. As discussed below, it could be that the states have conflicting estimates of the likelihood of victory, and if both sides are optimistic about their chances this can obscure the bargaining range. But even if the states have private and conflicting estimates of what would happen in a war, if they are rational, they should know that there can be only one true probability that one or the other will prevail (perhaps different from their own estimate). Thus rational states should know that there must in fact exist a set of agreements all prefer to a fight.
这一结果需要三个实质性假设，其中没有一个似乎特别有力。首先，各国都知道，在军事较量中，一国获胜的概率 $p$$p$pp 是真实存在的。正如下文所讨论的，各国对获胜可能性的估计可能存在冲突，如果双方都对自己的胜算持乐观态度，就会模糊讨价还价的范围。但是，即使各国对战争中会发生什么有私人的、相互矛盾的估计，如果它们是理性的，它们就应该知道，一方或另一方获胜的真实概率只有一个（可能与它们自己的估计不同）。因此，理性的国家应该知道，事实上一定存在一套协议，所有协议都倾向于战争。

Second, it is assumed that the states are risk-averse or risk-neutral over the issues. Because risk attitude is defined relative to an underlying metric (such as money in economics), the substantive meaning of this assumption depends on the bargaining context. Loosely, it says that the states prefer a fifty-fifty split or share of whatever is at issue (in whatever metric it comes, if any) to a fifty-fifty chance at all or nothing, where this refers to the value of winning or losing a war. In effect, the assumption means that leaders do not like gambling when the downside risk is losing at war, which seems plausible given the presumption that state leaders normally wish to retain territory and power. A risk-acceptant leader is analogous to a compulsive gambler-willing to accept a sequence of gambles that has the expected outcome of eliminating the state and regime. Even if we admitted such a leader as rational, it seems doubtful that many have held such preferences (Hitler being a possible exception).
其次，假设各国在这些问题上都是规避风险或风险中性的。由于风险态度的定义是相对于一个基本指标（如经济学中的货币）而言的，因此这一假设的实质含义取决于讨价还价的背景。从广义上讲，它指的是国家更倾向于五五分成或分享有争议的东西（无论以何种标准衡量，如果有的话），而不是五五分成的机会，这里的五五分成指的是战争输赢的价值。实际上，这一假设意味着，当战争失败的负面风险时，领导人不喜欢赌博，鉴于国家领导人通常希望保住领土和权力，这一假设似乎是可信的。接受风险的领导人类似于强迫性赌徒--愿意接受一连串的赌博，其预期结果是消灭国家和政权。即使我们承认这样的领导人是理性的，但是否有很多人持有这样的偏好（希特勒可能是个例外）似乎也值得怀疑。

Finally, it was assumed that a continuous range of peaceful settlements (from 0 to 1) exists. In other words, the issues in dispute are perfectly divisible, so that there are always feasible bargains between the states’ reservation levels $p-c_A$$p-c_A$p-c_(A)p-c_{A} and $p+c_B$$p+c_B$p+c_(B)p+c_{B}. This third assumption immediately suggests a tenable rationalist explanation for war. Perhaps something about the nature of some international issues, such as which successor will sit on a throne, does not admit finely graded divisions and compromise. If so, then small costs for fighting and bad luck may make for rational war over such issues.
最后，假设存在一个连续的和平解决范围（从 0 到 1）。换句话说，有争议的问题是完全可分的，因此在各国的保留水平 $p-c_A$$p-c_A$p-c_(A)p-c_{A} 和 $p+c_B$$p+c_B$p+c_(B)p+c_{B} 之间总是存在可行的讨价还价。第三个假设立即为战争提供了一个合理的解释。也许某些国际问题的本质，比如哪位继承人将坐上王位，并不允许精细分级的分歧和妥协。如果是这样，那么小的战斗成本和坏运气可能会使人们在这些问题上理性地进行战争。

But we would immediately like to know what about the nature of an issue makes it impossible to divide up. On more thought, this seems empirically implausible. In the first place, most issues states negotiate over are quite complex-they have many dimensions of concern and allow many possible settlements. Second, if states can simply pay each other sums of money or goods (which they can, in principle), or make linkages with other issues, then this should have the effect of making any issues in dispute perfectly divisible. Before the age of nationalism, princes often bought, sold, and partitioned land. ${}^{17}$${}^{17}$^(17){ }^{17} In the nineteenth century the United States purchased the Louisiana territory from France, and Alaska from Russia, and as late as 1898 President McKinley explored the possibility of buying Cuba from Spain in order to avoid a war over it. ${}^{18}$${}^{18}$^(18){ }^{18} Third, if something about the nature of an issue means that it can be settled in only, say, two ways, then some sort of random allocation or alternation between the two resolutions could in principle serve to create intermediate bargains. Mafia dons, for example, apparently have avoided costly internal wars by using lotteries to allocate construction contracts among families. ${}^{19}$${}^{19}$^(19){ }^{19}
但是，我们马上就想知道，问题的本质是什么使得它无法分割。再仔细一想，这在经验上似乎不太可信。首先，大多数国家谈判的问题都相当复杂--它们涉及许多方面，有许多可能的解决方案。其次，如果各国可以简单地相互支付金钱或货物（原则上可以），或与其他问题挂钩，那么这就会使任何有争议的问题变得完全可分。在民族主义时代之前，王公们经常买卖和分割土地。 ${}^{17}$${}^{17}$^(17){ }^{17} 19世纪，美国从法国购买了路易斯安那领土，从俄国购买了阿拉斯加，直到1898年，麦金利总统还在探讨从西班牙购买古巴的可能性，以避免为古巴爆发战争。 ${}^{18}$${}^{18}$^(18){ }^{18} 第三，如果一个问题的性质意味着它只能通过两种方式来解决，那么某种随机分配或两种解决方案之间的交替原则上可以用来创造中间交易。例如，黑手党的头目们显然通过在家族间分配建筑合同的抽签方式避免了代价高昂的内战。 ${}^{19}$${}^{19}$^(19){ }^{19} .
In practice, creating intermediate settlements with cash, with linkages to other issues, or with randomization or alternation often seems difficult or impossible for states engaged in a dispute. For example, the immediate issue that gave rise to the Franco-Prussian war was a dispute over which prince would take the Spanish throne. It doubtless occurred to no one to propose that the two candidates alternate year by year, or three years for the Hapsburg and one for the Hohenzollern, or whatever. In this case as in many others, the issue could in principle have been made more continuous and was not for other reasons-here, alternating kings would have violated so many conventions and norms as to have been domestically unworkable. To give a more realistic
在实践中，对于卷入争端的国家来说，用现金、与其他问题的联系、随机化或交替的方式来建立中间解决方案往往显得困难或不可能。例如，引起普法战争的直接问题是关于由哪位王子继承西班牙王位的争端。毫无疑问，没有人提议让两位候选人逐年交替，或者哈布斯堡王朝三年一任，霍亨索伦王朝三年一任等等。在这种情况下，正如在其他许多情况下一样，原则上可以使问题更具连续性，但由于其他原因而没有这样做--在这种情况下，国王轮流制会违反许多惯例和规范，在国内是行不通的。为了更切合实际

example, nineteenth- and twentieth-century leaders cannot divide up and trade territory in international negotiations as easily as could rulers in the seventeenth and eighteenth centuries, due in part to domestic political consequences of the rise of nationalism; contrast, for example, the Congress of Vienna with the negotiations following World War I.
例如，19 世纪和 20 世纪的领导人在国际谈判中不能像 17 世纪和 18 世纪的统治者那样轻易地划分和交易领土，部分原因是民族主义兴起造成的国内政治后果；例如，维也纳会议与第一次世界大战后的谈判形成鲜明对比。

So in principle the indivisibility of the issues that are the subject of international bargaining can provide a coherent rationalist explanation for war. However, the real question in such cases is what prevents leaders from creating intermediate settlements, and the answer is likely to be other mechanisms (often domestic political) rather than the nature of the issues themselves. ${}^{20}$${}^{20}$^(20){ }^{20} Both the intrinsic complexity and richness of most matters over which states negotiate and the availability of linkages and side-payments suggest that intermediate bargains typically will exist.
因此，原则上，作为国际谈判主题的问题的不可分割性可以为战争提供一个连贯的理性主义解释。然而，在这种情况下，真正的问题在于是什么阻碍了领导人达成中间解决方案，而答案很可能是其他机制（通常是国内政治机制），而不是问题本身的性质。 ${}^{20}$${}^{20}$^(20){ }^{20} 国家谈判所涉及的大多数问题的内在复杂性和丰富性，以及联系和附带报酬的存在，都表明中间交易通常会存在。

It is thus not sufficient to say that positive expected utility by itself supplies a coherent or compelling rationalist explanation for war. Provided that the issues in dispute are sufficiently divisible, or that side-payments are possible, there should exist a set of negotiated agreements that have greater utility for both sides than the gamble of war does. The reason is that the ex post inefficiency of war opens up an ex ante bargaining range.
因此，仅仅说正期望效用本身为战争提供了一个连贯或令人信服的理性主义解释是不够的。只要争论的问题有足够的可分割性，或者说附带报酬是可能的，那么就应该存在一组谈判达成的协议，这些协议对双方的效用都要大于战争的赌博效用。原因在于，战争的事后无效率开辟了一个事前讨价还价的范围。

So, to explain how war could occur between rationally led states, we need to answer the following question. Given the existence of an ex ante bargaining range, why might states fail either to locate or to agree on an outcome in this range, so avoiding the costs and risks of war?
因此，要解释理性主导的国家之间为何会发生战争，我们需要回答以下问题。既然存在一个事前讨价还价的范围，为什么各国可能无法在这个范围内找到或商定一个结果，从而避免战争的代价和风险？

Two commonly employed rationalist explanations in the literature directly address the preceding question. Both turn on the claim that war can be and often is the product of rational miscalculation. One explanation holds that a state’s leaders may rationally overestimate their chance of military victory against an adversary, so producing a disagreement about relative power that only war can resolve. The other argues that rationally led states may lack information about an adversary’s willingness to fight over some interest and so may challenge in the mistaken belief that war will not follow.
文献中两种常用的理性主义解释直接涉及了上述问题。这两种解释都基于这样一种主张，即战争可能是而且往往是理性误判的产物。一种解释认为，一个国家的领导人可能会理性地高估自己在军事上战胜对手的机会，从而产生只有战争才能解决的相对实力分歧。另一种解释则认为，理性领导的国家可能缺乏关于对手是否愿意为某些利益而战的信息，因此可能误以为战争不会随之而来，从而提出挑战。

In this section I argue that while these ideas point toward a tenable rationalist explanation for war, neither goes far enough and neither works by itself. Both neglect the fact that states can in principle communicate with each other and so avoid a costly miscalculation of relative power or will. The cause of
在本节中，我将论证，虽然这些观点都指向对战争的合理解释，但两者都不够深入，也都不能单独发挥作用。两者都忽略了一个事实，即各国原则上可以相互沟通，从而避免对相对实力或意愿的错误判断，而这种错误判断代价高昂。战争的原因

war cannot be simply lack of information, but whatever it is that prevents its disclosure. I argue that the fact that states have incentives to misrepresent their positions is crucial here, explaining on rationalist terms why diplomacy may not allow rational states to clarify disagreements about relative power or to avoid the miscalculation of resolve.
战争的原因不能仅仅是缺乏信息，而是任何阻碍信息披露的因素。我认为，国家有动机歪曲自己的立场这一事实在这里至关重要，它从理性主义的角度解释了为什么外交可能无法让理性的国家澄清关于相对实力的分歧或避免对决心的误判。

The mainstream international relations literature recognizes the existence of both private information and incentives to misrepresent, but typically views them as background conditions to be taken for granted rather than as key elements of an explanation of how rationally led states might end up at war. For example, Jack Levy’s impressive review of the literature on the causes of war contains nothing on the role of incentives to misrepresent and discusses private information largely in the context of misperceptions of other states’ intentions (which are linked to psychological biases). This is an accurate reflection of where these factors stand in the mainstream literature. ${}^{21}$${}^{21}$^(21){ }^{21}
主流国际关系文献承认私人信息和虚假陈述动机的存在，但通常将它们视为理所当然的背景条件，而不是解释理性主导的国家如何最终爆发战争的关键因素。例如，杰克-利维（Jack Levy）对战争原因的文献回顾令人印象深刻，其中没有任何关于虚假陈述动机作用的内容，而且主要是在对其他国家意图的误解（这与心理偏见有关）的背景下讨论私人信息的。这准确地反映了这些因素在主流文献中的地位。 ${}^{21}$${}^{21}$^(21){ }^{21}

Geoffrey Blainey’s well-known and often-cited argument is that "wars usually begin when two nations disagree on their relative strength. ${}^{\prime 22}$${}^{\prime 22}$^('22){ }^{\prime 22} It is easy to see how a disagreement about relative strength—understood as conflicting estimates of the likelihood of military victory-can eliminate any ex ante bargaining range. Recall the example given above, where two states bargain over the division of $\mathrm{\$}100$$\mathrm{\$}100$$100\$ 100, and each has the outside option of going to war. If each expects that it surely would prevail at war, then each side’s expected value for the war option is $\mathrm{\$}80(1\cdot 100+0\cdot 0-20)$$\mathrm{\$}80(1\cdot 100+0\cdot 0-20)$$80(1*100+0*0-20)\$ 80(1 \cdot 100+0 \cdot 0-20). So given these expectations, neither side will accept less than $\mathrm{\$}80$$\mathrm{\$}80$$80\$ 80 in the bargaining, implying that no negotiated outcome is mutually preferred to war. More generally, suppose that state A expects to win with probability $p$$p$pp, state B expects to win with probability $r$$r$rr, and $p$$p$pp and $r$$r$rr sum to greater than one. Such conflicting expectations will certainly shrink and could eliminate any ex ante bargaining range.
杰弗里-布莱尼（Geoffrey Blainey）提出了一个众所周知且经常被引用的论点："战争通常始于两国在相对实力上的分歧。 ${}^{\prime 22}$${}^{\prime 22}$^('22){ }^{\prime 22} 不难看出，对相对实力的分歧--可以理解为对军事胜利可能性的相互矛盾的估计--是如何消除任何事前讨价还价范围的。回顾上面的例子，两个国家就 $\mathrm{\$}100$$\mathrm{\$}100$$100\$ 100 的分割进行讨价还价，每个国家都有开战的外部选择。如果每一方都预期自己肯定会在战争中获胜，那么每一方对战争选项的预期值就是 $\mathrm{\$}80(1\cdot 100+0\cdot 0-20)$$\mathrm{\$}80(1\cdot 100+0\cdot 0-20)$$80(1*100+0*0-20)\$ 80(1 \cdot 100+0 \cdot 0-20) 。因此，考虑到这些预期，任何一方都不会在讨价还价中接受小于 $\mathrm{\$}80$$\mathrm{\$}80$$80\$ 80 的结果，这意味着没有任何谈判结果比战争更受双方青睐。更广义地说，假设甲国预期获胜的概率为 $p$$p$pp ，乙国预期获胜的概率为 $r$$r$rr ，且 $p$$p$pp 和 $r$$r$rr 之和大于1。这种相互冲突的预期肯定会缩小并可能消除任何事前讨价还价的范围。

But how could rationally led states have conflicting expectations about the likely outcome of military conflict? In the extreme case, how could both sides rationally expect to win? The literature barely addresses this question in
但是，理性的国家怎么会对军事冲突的可能结果抱有相互冲突的预期呢？在极端情况下，双方又如何能理性地预期获胜呢？文献中几乎没有涉及这个问题

explicit terms. Blainey, whom the literature views as advancing a rationalist explanation for war, in fact explains disagreements about relative power as a consequence of human irrationality. He says that mutual optimism about victory in war is the product of “moods which cannot be grounded in fact” and which “permeate what appear to be rational assessments of the relative military strength of two contending powers.” Mutual optimism is said to result from a “process by which nations evade reality,” which hardly sounds like a rationalist explanation. ${}^{23}$${}^{23}$^(23){ }^{23}
明确的术语。文献认为布雷尼对战争提出了理性主义的解释，但事实上，他把对相对实力的分歧解释为人类非理性的结果。他说，对战争胜利的相互乐观是 "无法建立在事实基础上的情绪 "的产物，这种情绪 "渗透在对两个竞争大国相对军事实力的看似理性的评估中"。相互乐观主义被认为是 "国家逃避现实的过程 "的结果，这听起来不像是理性主义的解释。 ${}^{23}$${}^{23}$^(23){ }^{23}

Conflicting expectations about the likely outcome of military conflict may be explained in three ways. First, as Blainey suggests, emotional commitments could irrationally bias leaders’ military estimates. They might, for instance, come to believe nationalist rhetoric holding that their soldiers are more courageous and spirited than those of the adversary. ${}^{24}$${}^{24}$^(24){ }^{24} Second, the world is a very complex place, and for this reason military analysts in different states could reach different conclusions about the likely impact of different technologies, doctrines, and tactics on the expected course of battle. Third, state leaders might have private information about militarily relevant factors-military capabilities, strategy, and tactics; the population’s willingness to prosecute a long war; or third-state intentions. If a state has superior (and so private) information about any such factor, then its estimate of the probable course of battle may differ from that of an adversary.
对军事冲突可能出现的结果的矛盾预期可以从三个方面来解释。首先，正如布雷尼所言，情感承诺可能会不合理地影响领导人对军事结果的估计。例如，他们可能会相信民族主义言论，认为自己的士兵比对手的士兵更勇敢、更有精神。 ${}^{24}$${}^{24}$^(24){ }^{24} 其次，世界是一个非常复杂的地方，因此，不同国家的军事分析家可能会就不同技术、理论和战术对预期战斗进程可能产生的影响得出不同的结论。第三，国家领导人可能掌握军事相关因素的私人信息--军事能力、战略和战术；民众进行长期战争的意愿；或第三国的意图。如果一个国家拥有关于任何此类因素的优势信息（因此也是私人信息），那么它对可能的战争进程的估计就可能与对手不同。

Under a strict but standard definition of rationality, only the third explanation qualifies as an account of how rationally led states could have conflicting estimates of the probability of winning in war. As argued by John Harsanyi, if two rational agents have the same information about an uncertain event, then they should have the same beliefs about its likely outcome. ${}^{25}$${}^{25}$^(25){ }^{25} The claim is that given identical information, truly rational agents should reason to the same conclusions about the probability of one uncertain outcome or another. Conflicting estimates should occur only if the agents have different (and so necessarily private) information. ${}^{26}$${}^{26}$^(26){ }^{26}
根据理性的严格但标准的定义，只有第三种解释才有资格解释理性领导的国家为何会对战争获胜的概率有相互矛盾的估计。正如约翰-哈桑尼（John Harsanyi）所论证的那样，如果两个理性主体对某一不确定事件拥有相同的信息，那么他们就应该对事件的可能结果拥有相同的信念。 ${}^{25}$${}^{25}$^(25){ }^{25} 其主张是，在信息完全相同的情况下，真正理性的代理人应该对一种或另一种不确定结果的概率得出相同的推理结论。只有当代理人拥有不同的（因此必然是私人的）信息时，才会出现相互矛盾的估计。 ${}^{26}$${}^{26}$^(26){ }^{26}

It follows that the second explanation for disagreements about relative power listed above-the complexity of the world-is not a rationalist account. Instead, it is an account that explains conflicting military estimates as a consequence of bounded rationality. In this view, leaders or military analysts with the same information about military technology, strategy, political will, etc. might reason to different conclusions about the likely course of a war because of differential ability to cope with complexity of the problem. This is entirely plausible, but it is a bounded rationality explanation rather than a fully rationalist one. ${}^{27}$${}^{27}$^(27){ }^{27}
由此可见，上述对相对实力分歧的第二种解释--世界的复杂性--并不是理性主义的解释。相反，它是一种将相互冲突的军事估计解释为有限理性的结果的解释。根据这种观点，在军事技术、战略、政治意愿等方面拥有相同信息的领导人或军事分析家，可能会因为应对问题复杂性的能力不同而对战争的可能进程得出不同的结论。这是完全有道理的，但这只是一种有界理性的解释，而不是完全理性主义的解释。 ${}^{27}$${}^{27}$^(27){ }^{27}

The rationalist account of how disagreements about the probability of winning might arise also seems empirically plausible. States certainly have private information about factors affecting the likely course of battle-for example, they jealously guard military secrets and often have superior information about what an ally will or will not fight for. Nonetheless, while private information about militarily relevant capabilities provides a first step, it does not provide a coherent rationalist explanation for war. The problem is that even if leaders have such private information, they should understand that their own estimates based on this information are suspect because they do not know the other side’s private information. In principle, both sides could gain by sharing information, which would yield a consensus military estimate (absent bounded rationality). And, as shown above, doing so could not help but reveal bargains that both would prefer to a fight. ${}^{28}$${}^{28}$^(28){ }^{28}
理性主义关于获胜概率的分歧如何产生的论述在经验上似乎也是可信的。国家当然掌握着影响可能的战斗进程的私人信息--例如，它们严守军事机密，而且往往掌握着关于盟友会为或不会为什么而战的优势信息。然而，虽然关于军事相关能力的私人信息提供了第一步，但它并不能为战争提供一个连贯的理性主义解释。问题在于，即使领导人掌握了这些私人信息，他们也应该明白，自己根据这些信息做出的估计是可疑的，因为他们不知道对方的私人信息。原则上，双方都可以通过共享信息而获益，这样就能达成一致的军事估计（不存在有界理性）。而且，如上文所示，这样做也会揭示出双方都希望达成的协议，而不是一场战斗。 ${}^{28}$${}^{28}$^(28){ }^{28}

So the question of how rationally led states can disagree about relative power devolves to the question of what prevents states from sharing private information about factors that might affect the course of battle. Before turning to this question, I will consider the second common explanation for how a rational miscalculation may produce war.
因此，关于理性主导的国家如何在相对实力问题上产生分歧的问题，就变成了是什么阻止了国家分享可能影响战争进程的因素的私人信息。在探讨这个问题之前，我将考虑理性误判如何导致战争的第二种常见解释。

Many wars have been given the following so-called rationalist explanation: state A transgressed some interest of state B in the erroneous belief that B would not fight a war over the matter. Though rationally led, state A lacked information about B’s willingness to fight and simply happened to guess wrong, causing a war. Thus, some say that Germany miscalculated Russian and/or British willingness to fight in 1914; Hitler miscalculated Britain and France’s
许多战争都有如下所谓的理性主义解释：甲国错误地认为乙国不会就此事开战，从而侵犯了乙国的某些利益。虽然甲国是理性的，但它缺乏关于乙国是否愿意打仗的信息，只是碰巧猜错了，从而引发了战争。因此，有人说德国在 1914 年错误地估计了俄国和/或英国的战争意愿；希特勒错误地估计了英国和法国的战争意愿。

willingness to resist his drive to the east; Japanese leaders in 1941 miscalculated U.S. willingness to fight a long war over control in the South Pacific; North Korea miscalculated U.S. willingness to defend South Korea; the United States miscalculated China’s willingness to defend North Korea; and so on. In each case, the argument would hold that lack of information led a more-or-less rational actor to guess wrong about the extent of the bargaining range.
1941年，日本领导人错误估计了美国为争夺南太平洋控制权而进行长期战争的意愿；朝鲜错误估计了美国保卫南朝鲜的意愿；美国错误估计了中国保卫朝鲜的意愿；等等。在每种情况下，都会有这样的论点，即由于缺乏信息，一个或多或少理性的行为者对讨价还价的范围猜错了。

Blainey has argued that if states agree on relative power they are very unlikely to go to war against each other. ${}^{29}$${}^{29}$^(29){ }^{29} It is worth pointing out that in the preceding argument, war can occur despite complete agreement on relative power across states. To show how and for later use, I will introduce a simple model of international bargaining. As in the empirical examples just mentioned, in the model one state unilaterally chooses some revision of the status quo. The second state can then either acquiesce to the revision or can go to war to reverse it.
布莱尼认为，如果各国在相对实力问题上达成一致，它们就不太可能相互开战。 ${}^{29}$${}^{29}$^(29){ }^{29} 值得指出的是，在前面的论证中，尽管各国在相对实力上完全一致，战争也可能发生。为了说明这一点，我将引入一个简单的国际讨价还价模型。与刚才提到的实证例子一样，在这个模型中，一个国家单方面选择对现状进行某种修正。然后，第二个国家既可以默许这种修改，也可以发动战争来扭转局面。

Formally, suppose there is a status quo resolution of the issues $q\in X$$q\in X$q in Xq \in X and that state A has the opportunity to choose any outcome $x\in X$$x\in X$x in Xx \in X, presenting state $B$$B$BB with a fait accompli. On observing what state A did (which might be nothing, i.e., $x=q$$x=q$x=qx=q ), state B can choose whether to go to war or to acquiesce to A’s revision of the status quo.
从形式上看，假设问题的解决现状是 $q\in X$$q\in X$q in Xq \in X ，A 国有机会选择任何结果 $x\in X$$x\in X$x in Xx \in X ，给 B 国带来既成事实 $B$$B$BB 。在观察到 A 国的所作所为（可能什么也没做，即 $x=q$$x=q$x=qx=q ）后，B 国可以选择是开战还是默认 A 国对现状的修正。
If neither state has any private information, so that all payoffs are common knowledge, state A does best to push the outcome just up to B’s reservation level $p+c_B$$p+c_B$p+c_(B)p+c_{B}, which makes B just willing to acquiesce rather than go to war. With complete information, then, the states avoid the inefficient outcome of war. ${}^{30}$${}^{30}$^(30){ }^{30} On the other hand, if state B has private information about either its capabilities (which affect $p$$p$pp ) or its value for the issues at stake relative to the costs of conflict $\left(c_B\right)$$\left(c_B\right)$(c_(B))\left(c_{B}\right), then state A may not know whether a particular “demand” $x$$x$xx will yield war or peace. Lacking this information, state A faces a trade-off in deciding whether and how much territory to “grab”: The larger the grab, the greater the risk of war, but the better off A will be if state B acquiesces.
如果两国都没有任何私人信息，因此所有的报酬都是共同的知识，那么甲国就会尽力将结果推高到乙国的保留水平 $p+c_B$$p+c_B$p+c_(B)p+c_{B} ，这使得乙国只愿意默许而不愿意开战。因此，在完全知情的情况下，各国都会避免战争这种低效率的结果。 ${}^{30}$${}^{30}$^(30){ }^{30} 另一方面，如果乙国拥有关于其能力（这会影响 $p$$p$pp ）或相对于冲突成本 $\left(c_B\right)$$\left(c_B\right)$(c_(B))\left(c_{B}\right) 的利害问题价值的私人信息，那么甲国可能不知道特定的 "需求" $x$$x$xx 会带来战争还是和平。由于缺乏这方面的信息，A 国在决定是否 "抢夺 "以及抢夺多少领土时就会面临取舍：攫取的领土越大，战争的风险就越大，但如果乙国默许，甲国就会过得更好。
Suppose, for example, that A and B share a common estimate of $p$$p$pp-they agree about relative power-but that A is unsure about B’s costs fo