I

We have seen in the previous chapter that the scale of investment depends on the relation between the rate of interest and the schedule of the marginal efficiency of capital corresponding to different scales of current investment, whilst the marginal efficiency of capital depends on the relation between the supply price of a capital-asset and its prospective yield. In this chapter we shall consider in more detail some of the factors which determine the prospective yield of an asset.

我们在前一章已经看到，投资规模取决于利率与边际资本效率表之间的关系，而这个边际资本效率表对应于当前投资的不同规模；与此同时，资本的边际效率又取决于资本资产的供给价格与其预期收益之间的关系。在本章中，我们将更详细地考察决定一项资产预期收益的若干因素。

The considerations upon which expectations of prospective yields are based are partly existing facts which we can assume to be known more or less for certain, and partly future events which can only be forecasted with more or less confidence. Amongst the first may be mentioned the existing stock of various types of capital-assets and of capital-assets in general and the strength of the existing consumers' demand for goods which require for their efficient production a relatively larger assistance from capital. Amongst the latter are future changes in the type and quantity of the stock of capital-assets and in the tastes of the consumer, the strength of effective demand from time to time during the life of the investment under consideration, and the changes in the wage-unit in terms of money which may occur during its life. We may sum up the state of psychological expectation which covers the latter as being the state of long-term expectation;¾as distinguished from the short-term expectation upon the basis of which a producer estimates what he will get for a product when it is finished if he decides to begin producing it to-day with the existing plant, which we examined in chapter 5.

作为预期收益基础的考量，一部分是现存事实，这些事实我们可以认为是或多或少较为确定地已知的；另一部分则是未来事件，这些事件只能以或多或少的信心加以预测。前者包括：现有的各种类型资本资产的存量，以及资本资产总体的存量；还包括现有消费者对那些在有效生产中相对更依赖资本辅助的商品之需求强度。后者则包括：未来资本资产存量在类型和数量上的变化、消费者偏好的变化、所考察投资在其存续期间各个时点上的有效需求强度，以及其存续期间内以货币计量的工资单位可能发生的变化。我们可以把涵盖后者的这种心理预期状态，总结为长期预期状态；它有别于短期预期，后者是生产者在决定今天利用现有设备开始生产时，用来估计产品完工后能卖到什么价格的依据，这一点我们已在第5章讨论过。

II

It would be foolish, in forming our expectations, to attach great weight to matters which are very uncertain. It is reasonable, therefore, to be guided to a considerable degree by the facts about which we feel somewhat confident, even though they may be less decisively relevant to the issue than other facts about which our knowledge is vague and scanty. For this reason the facts of the existing situation enter, in a sense disproportionately, into the formation of our long-term expectations; our usual practice being to take the existing situation and to project it into the future, modified only to the extent that we have more or less definite reasons for expecting a change.

在形成预期时，对那些极不确定的事项赋予很大权重，是愚蠢的。因此，在相当程度上让那些我们多少有些把握的事实来引导我们，是合理的；即使这些事实相较于另一些我们所知模糊而贫乏的事实，对问题本身的相关性未必更具决定性。正因如此，现状事实在某种意义上会以一种不成比例的方式进入我们长期预期的形成过程；我们通常的做法是，把现有状况向未来加以延伸，只有在我们有或多或少明确的理由预期会发生变化时，才对这种延伸作出修正。

The state of long-term expectation, upon which our decisions are based, does not solely depend, therefore, on the most probable forecast we can make. It also depends on the confidence with which we make this forecast¾on how highly we rate the likelihood of our best forecast turning out quite wrong. If we expect large changes but are very uncertain as to what precise form these changes will take, then our confidence will be weak.

因此，作为我们决策依据的长期预期状态，并不只取决于我们所能作出的那个“最可能”的预测。它还取决于我们作出这一预测时所具有的信心——也就是，我们如何评估自己这个最佳预测最终被证明大错特错的可能性有多高。如果我们预期会有重大变化，但又对这些变化究竟会采取何种具体形式极不确定，那么我们的信心就会很弱。

The state of confidence, as they term it, is a matter to which practical men always pay the closest and most anxious attention. But economists have not analysed it carefully and have been content, as a rule, to discuss it in general terms. In particular it has not been made clear that its relevance to economic problems comes in through its important influence on the schedule of the marginal efficiency of capital. There are not two separate factors affecting the rate of investment, namely, the schedule of the marginal efficiency of capital and the state of confidence. The state of confidence is relevant because it is one of the major factors determining the former, which is the same thing as the investment demand-schedule.

所谓“信心状态”，正如他们所称，是实务界人士始终给予最密切、最焦虑关注的问题。但经济学家并没有对它作出仔细分析，通常只是满足于用一般性的语言来讨论它。尤其是，人们并没有清楚说明，它之所以与经济问题相关，是因为它会对资本边际效率表产生重要影响。影响投资率的，并不是两个彼此独立的因素——即资本边际效率表和信心状态。信心状态之所以重要，是因为它本身就是决定前者的主要因素之一，而前者其实就是投资需求表。

There is, however, not much to be said about the state of confidence a priori. Our conclusions must mainly depend upon the actual observation of markets and business psychology. This is the reason why the ensuing digression is on a different level of abstraction from most of this book.

不过，关于信心状态，先验地并没有太多可说。我们的结论主要必须依赖于对市场和商业心理的实际观察。这也就是为什么接下来这一段插论，在抽象层次上不同于本书大部分内容。

For convenience of exposition we shall assume in the following discussion of the state of confidence that there are no changes in the rate of interest; and we shall write, throughout the following sections, as if changes in the values of investments were solely due to changes in the expectation of their prospective yields and not at all to changes in the rate of interest at which these prospective yields are capitalised. The effect of changes in the rate of interest is, however, easily superimposed on the effect of changes in the state of confidence.

为了行文方便，在下面关于信心状态的讨论中，我们将假定利率没有发生变化；并且在接下来的各节中，我们都将按照这样的方式来写：仿佛投资价值的变化，完全是由其预期收益之预期发生变化所致，而丝毫不是由于将这些预期收益资本化时所采用的利率发生变化所致。不过，利率变化的影响，很容易叠加到信心状态变化的影响之上。

III

The outstanding fact is the extreme precariousness of the basis of knowledge on which our estimates of prospective yield have to be made. Our knowledge of the factors which will govern the yield of an investment some years hence is usually very slight and often negligible. If we speak frankly, we have to admit that our basis of knowledge for estimating the yield ten years hence of a railway, a copper mine, a textile factory, the goodwill of a patent medicine, an Atlantic liner, a building in the City of London amounts to little and sometimes to nothing; or even five years hence. In fact, those who seriously attempt to make any such estimate are often so much in the minority that their behaviour does not govern the market.

最突出的事实是：我们用来估计预期收益的知识基础，极其脆弱。对于若干年后将决定某项投资收益的那些因素，我们所掌握的知识通常极其有限，往往可以忽略不计。坦率地说，我们必须承认：无论是铁路、铜矿、纺织厂、某种专利药的商誉、一艘横渡大西洋的远洋轮船，还是伦敦金融城的一栋大楼，要估计它们十年后的收益，我们所依据的知识基础少得可怜，有时甚至等于没有；即便是五年后的收益，也同样如此。事实上，那些真正认真尝试作出此类估计的人，往往只是极少数，因此他们的行为并不能支配市场。

In former times, when enterprises were mainly owned by those who undertook them or by their friends and associates, investment depended on a sufficient supply of individuals of sanguine temperament and constructive impulses who embarked on business as a way of life, not really relying on a precise calculation of prospective profit. The affair was partly a lottery, though with the ultimate result largely governed by whether the abilities and character of the managers were above or below the average. Some would fail and some would succeed. But even after the event no one would know whether the average results in terms of the sums invested had exceeded, equalled or fallen short of the prevailing rate of interest; though, if we exclude the exploitation of natural resources and monopolies, it is probable that the actual average results of investments, even during periods of progress and prosperity, have disappointed the hopes which prompted them. Business men play a mixed game of skill and chance, the average results of which to the players are not known by those who take a hand. If human nature felt no temptation to take a chance, no satisfaction (profit apart) in constructing a factory, a railway, a mine or a farm, there might not be much investment merely as a result of cold calculation.

在较早的时候，当企业主要归属于创办者本人，或者其朋友与合伙人所有时，投资取决于是否有足够多的人具备乐观的气质和建设性的冲动，把经营事业当作一种生活方式来投入，而并不真正依赖对未来利润的精确计算。这件事在某种程度上像一场彩票，尽管最终结果在很大程度上仍取决于管理者的能力和品格究竟高于还是低于平均水平。有些人会失败，有些人会成功。但即便事后，也没有人知道，就投入金额而言，平均结果究竟是高于、等于，还是低于当时通行的利率；不过，如果我们把自然资源开发和垄断剔除在外，那么很可能，投资的实际平均结果，即使在进步与繁荣时期，也仍然低于当初促使人们去投资的那些希望。商人参与的是一种技巧与运气混合的游戏，而参与其中的人并不知道这场游戏对所有参与者的平均结果究竟如何。如果人性对于碰运气毫无诱惑感，对于建造工厂、铁路、矿山或农场这类事情也得不到任何满足感（撇开利润不谈），那么单凭冷冰冰的计算，投资恐怕不会很多。

Decisions to invest in private business of the old-fashioned type were, however, decisions largely irrevocable, not only for the community as a whole, but also for the individual. With the separation between ownership and management which prevails to-day and with the development of organised investment markets, a new factor of great importance has entered in, which sometimes facilitates investment but sometimes adds greatly to the instability of the system. In the absence of security markets, there is no object in frequently attempting to revalue an investment to which we are committed. But the Stock Exchange revalues many investments every day and the revaluations give a frequent opportunity to the individual (though not to the community as a whole) to revise his commitments. It is as though a farmer, having tapped his barometer after breakfast, could decide to remove his capital from the farming business between 10 and II in the morning and reconsider whether he should return to it later in the week. But the daily revaluations of the Stock Exchange, though they are primarily made to facilitate transfers of old investments between one individual and another, inevitably exert a decisive influence on the rate of current investment. For there is no sense in building up a new enterprise at a cost greater than that at which a similar existing enterprise can be purchased; whilst there is an inducement to spend on a new project what may seem an extravagant sum, if it can be floated off on the Stock Exchange at an immediate profit. Thus certain classes of investment are governed by the average expectation of those who deal on the Stock Exchange as revealed in the price of shares, rather than by the genuine expectations of the professional entrepreneur. How then are these highly significant daily, even hourly, revaluations of existing investments carried out in practice?

然而，旧式私人企业中的投资决策，在很大程度上是不可撤销的，不仅对整个社会如此，对个人也是如此。随着当今所有权与经营权的分离，以及有组织投资市场的发展，一个极其重要的新因素进入了体系之中，它有时促进投资，有时却又大大增加体系的不稳定性。在没有证券市场的情况下，人们没有必要频繁地试图重新估值一项自己已经投入其中的投资。但证券交易所每天都在为许多投资重新定价，而这种重估让个人——虽然不是整个社会——有了频繁修正自己承诺的机会。这就好像一个农夫早饭后敲了敲气压计，便可以决定在上午10点到11点之间把资本从农业经营中撤出来，然后再考虑是否在本周稍后重新回去。但证券交易所的每日重估，虽然其首要目的是为了便利旧投资在个人之间转手，却不可避免地对当前投资率施加决定性影响。因为，如果创办一家新企业的成本高于购买一家类似现存企业的成本，那么去新建它就毫无意义；相反，如果一个新项目虽然看起来投入金额高得离谱，却能够在证券交易所上市后立刻获利，那么人们就会受到激励去投下这笔钱。因此，某些类型的投资，实际上是由证券交易所交易者通过股价所体现出来的平均预期来支配，而不是由职业企业家真正的预期来支配。那么，这种对现存投资进行的极其重要、每日甚至每小时发生的重估，在现实中究竟是如何完成的呢？

In practice we have tacitly agreed, as a rule, to fall back on what is, in truth, a convention. The essence of this convention¾though it does not, of course, work out quite so simply¾lies in assuming that the existing state of affairs will continue indefinitely, except in so far as we have specific reasons to expect a change. This does not mean that we really believe that the existing state of affairs will continue indefinitely. We know from extensive experience that this is most unlikely. The actual results of an investment over a long term of years very seldom agree with the initial expectation. Nor can we rationalise our behaviour by arguing that to a man in a state of ignorance errors in either direction are equally probable, so that there remains a mean actuarial expectation based on equi-probabilities. For it can easily be shown that the assumption of arithmetically equal probabilities based on a state of ignorance leads to absurdities. We are assuming, in effect, that the existing market valuation, however arrived at, is uniquely correct in relation to our existing knowledge of the facts which will influence the yield of the investment, and that it will only change in proportion to changes in this knowledge; though, philosophically speaking, it cannot be uniquely correct, since our existing knowledge does not provide a sufficient basis for a calculated mathematical expectation. In point of fact, all sorts of considerations enter into the market valuation which are in no way relevant to the prospective yield.

在实践中，通常我们都默认退回到一种其实就是“惯例”的东西上。这个惯例的本质——当然，现实运作并没有这么简单——在于假定现存状态会无限期持续下去，除非我们有某种明确理由预期它会改变。这并不意味着我们真的相信现存状态会永远持续。大量经验告诉我们，这种情况极不可能。一个投资在长期多年后的实际结果，极少会与最初预期一致。我们也不能通过这样一种说法来为自己的行为辩护：即对于一个处于无知状态的人来说，朝任一方向出错的概率相等，因此仍然存在一个建立在等概率基础上的平均精算预期。因为很容易证明，基于无知状态而假定算术意义上的等概率，会导出荒谬的结果。实际上，我们是在假定：现有市场估值，无论它是如何形成的，就我们现有关于那些将影响投资收益之事实的知识而言，是唯一正确的；并且它只会按我们这部分知识变化的比例而变化。可从哲学上说，它根本不可能是唯一正确的，因为我们现有的知识，并不足以为一种经过计算的数学期望提供充分基础。事实上，各种各样与未来收益毫不相关的因素，都会进入市场估值之中。

Nevertheless the above conventional method of calculation will be compatible with a considerable measure of continuity and stability in our affairs, so long as we can rely on the maintenance of the convention.

尽管如此，只要我们能够依赖这一惯例得以维持，上述这种惯例性的计算方法，仍然可以与我们事务中相当程度的连续性和稳定性相容。

For if there exist organised investment markets and if we can rely on the maintenance of the convention, an investor can legitimately encourage himself with the idea that the only risk he runs is that of a genuine change in the news over the near future, as to the likelihood of which he can attempt to form his own judgment, and which is unlikely to be very large. For, assuming that the convention holds good, it is only these changes which can affect the value of his investment, and he need not lose hiS sleep merely because he has not any notion what his investment will be worth ten years hence. Thus investment becomes reasonably 'safe' for the individual investor over short periods, and hence over a succession of short periods however many, if he can fairly rely on there being no breakdown in the convention and on his therefore having an opportunity to revise his judgment and change his investment, before there has been time for much to happen. Investments which are 'fixed' for the community are thus made 'liquid' for the individual.

因为，如果存在有组织的投资市场，并且我们能够依赖这一惯例得以维持，那么投资者就可以有理由安慰自己：他所承担的唯一风险，只是近期新闻发生真正变化的风险；对于这种变化发生的可能性，他可以尝试形成自己的判断，而这种变化通常也不至于很大。因为，只要假定这一惯例有效，也就只有这些变化才会影响他的投资价值；他不必仅仅因为自己并不知道十年后这项投资值多少钱，就因此夜不能寐。于是，对个人投资者来说，投资在短期内就变得相当“安全”；而如果他可以合理相信惯例不会崩溃，从而在很多事情真正发生之前，总有机会修正判断、调整投资，那么即使是一连串无数个短期，加总起来也同样如此。那些对社会而言是“固定”的投资，因此对个人而言却被变成了“流动”的。

It has been, I am sure, on the basis of some such procedure as this that our leading investment markets have been developed. But it is not surprising that a convention, in an absolute view of things so arbitrary, should have its weak points. It is its precariousness which creates no small part of our contemporary problem of securing sufficient investment.

我相信，我们那些主要投资市场，正是在某种类似这样的程序基础上发展起来的。但从绝对眼光看，这样一种本质上如此任意的惯例，必然会有其薄弱之处，这一点并不令人惊讶。正是这种惯例的脆弱性，构成了我们当代“如何确保足够投资”这一问题中相当重要的一部分。

Some of the factors which accentuate this precariousness may be briefly mentioned.

下面可以简要提及几项会加剧这种脆弱性的因素。

(1)  As a result of the gradual increase in the proportion of the equity in the community's aggregate capital investment which is owned by persons who do not manage and have no special knowledge of the circumstances, either actual or prospective, of the business in question, the element of real knowledge in the valuation of investments by whose who own them or contemplate purchasing them has seriously declined.

由于社会总体资本投资中的股权，越来越大比例掌握在那些既不参与经营、又对相关企业的现实情况和未来前景都没有专门知识的人手中，因而无论是持有这些投资的人，还是考虑购买这些投资的人，在估值时所依据的真实知识成分，都已严重下降。

(2)  Day-to-day fluctuations in the profits of existing investments, which are obviously of an ephemeral and non-significant character, tend to have an altogether excessive, and even an absurd, influence on the market. It is said, for example, that the shares of American companies which manufacture ice tend to sell at a higher price in summer when their profits are seasonally high than in winter when no one wants ice. The recurrence of a bank-holiday may raise the market valuation of the British railway system by several million pounds.

现有投资利润的日常波动，显然只是短暂的、并无实质意义的现象，但它们往往会对市场产生完全过度、甚至荒谬的影响。比如，据说美国制冰公司的股票，在夏季由于利润具有季节性高点，价格往往高于冬季——那时根本没人需要冰。一次银行假日的重复到来，就可能把英国铁路系统的市场估值抬高数百万英镑。

(3)  A conventional valuation which is established as the outcome of the mass psychology of a large number of ignorant individuals is liable to change violently as the result ofa sudden fluctuation of opinion due to factors which do not really make much difference to the prospective yield; since there will be no strong roots of conviction to hold it steady. In abnormal times in particular, when the hypothesis of an indefinite continuance of the existing state of affairs is less plausible than usual even though there are no express grounds to anticipate a definite change, the market will be subject to waves of optimistic and pessimistic sentiment, which are unreasoning and yet in a sense legitimate where no solid basis exists for a reasonable calculation.

一种由大量无知个体的群体心理所形成的惯例性估值，很容易因为某些其实并不会真正显著改变未来收益的因素，而在舆论突然波动时发生剧烈变化；因为并不存在强有力的信念根基来把它稳定住。尤其是在非常时期，即便并没有明确理由去预期某种确定变化，但“现状会无限期延续下去”这一假设也比平常更难成立，市场就会受到一波又一波乐观或悲观情绪的支配。这些情绪虽然不合逻辑，但在根本不存在坚实基础可供作出理性计算的地方，从某种意义上说又是“合理”的。

(4)  But there is one feature in particular which deserves our attention. It might have been supposed that competition between expert professionals, possessing judgment and knowledge beyond that of the average private investor, would correct the vagaries of the ignorant individual left to himself. It happens, however, that the energies and skill of the professional investor and speculator are mainly occupied otherwise. For most of these persons are, in fact, largely concerned, not with making superior long-term forecasts of the probable yield of an investment over its whole life, but with foreseeing changes in the conventional basis of valuation a short time ahead of the general public. They are concerned, not with what an investment is really worth to a man who buys it 'for keeps', but with what the market will value it at, under the influence of mass psychology, three months or a year hence. Moreover, this behaviour is not the outcome of a wrong-headed propensity. It is an inevitable result of an investment market organised along the lines described. For it is not sensible to pay 25 for an investment of which you believe the prospective yield to justify a value of 30, if you also believe that the market will value it at 20 three months hence.

但有一个特点尤其值得注意。人们本来可能会以为，那些判断力和知识都高于普通个人投资者的专业人士之间的竞争，会纠正无知个体单独行动时的种种偏差。然而事实是，职业投资者和投机者的精力与技巧，主要并不是用在这上面。因为这些人大多真正关心的，并不是对一项投资在其整个生命周期内的可能收益作出更高明的长期预测，而是预见在公众之前、短期内惯例性估值基础会如何变化。他们关心的，不是一项投资对那个打算“长期持有”的买家来说真正值多少钱，而是三个月后或一年后，在群体心理影响下，市场会给它定出什么价格。而且，这种行为并不是某种错误倾向的结果。它是按上述方式组织起来的投资市场的必然结果。因为，如果你相信某项投资按其未来收益本来值30，同时又相信三个月后市场会把它定价为20，那么现在花25去买它，就是不理性的。

Thus the professional investor is forced to concern himself with the anticipation of impending changes, in the news or in the atmosphere, of the kind by which experience shows that the mass psychology of the market is most influenced. This is the inevitable result of investment markets organised with a view to so-called 'liquidity'. Of the maxims of orthodox finance none, surely, is more anti-social than the fetish of liquidity, the doctrine that it is a positive virtue on the part of investment institutions to concentrate their resources upon the holding of 'liquid' securities. It forgets that there is no such thing as liquidity of investment for the community as a whole. The social object of skilled investment should be to defeat the dark forces of time and ignorance which envelop our future. The actual, private object of the most skilled investment to-day is 'to beat the gun', as the Americans so well express it, to outwit the crowd, and to pass the bad, or depreciating, half-crown to the other fellow.

因此，职业投资者被迫去关心那些即将发生的变化——无论是新闻上的变化，还是市场气氛上的变化——因为经验表明，市场的群体心理最容易受这类因素影响。这正是以所谓“流动性”为目标来组织投资市场的必然结果。在正统金融学的各种格言里，大概没有哪一条比“流动性崇拜”更反社会了——也就是把投资机构把资源集中配置在持有“流动性证券”上，当作一种积极美德的教条。它忘记了，对整个社会来说，根本不存在所谓投资的流动性。熟练投资在社会层面的目标，本应是战胜笼罩我们未来的时间与无知这两股黑暗力量。而今天最老练投资者在私人层面的真实目标，却是美国人说得很形象的那句话：“to beat the gun”——抢在别人前面出手，胜过人群，并把那枚劣质的、正在贬值的 half-crown 转手塞给下一个人。

This battle of wits to anticipate the basis of conventional valuation a few months hence, rather than the prospective yield of an investment over a long term of years, does not even require gulls amongst the public to feed the maws of the professional;¾it can be played by professionals amongst themselves. Nor is it necessary that anyone should keep his simple faith in the conventional basis of valuation having any genuine long-term validity. For it is, so to speak, a game of Snap, of Old Maid, of Musical Chairs¾a pastime in which he is victor who says Snap neither too soon nor too late, who passed the Old Maid to his neighbour before the game is over, who secures a chair for himself when the music stops. These games can be played with zest and enjoyment, though all the players know that it is the Old Maid which is circulating, or that when the music stops some of the players will find themselves unseated.

这种比拼机巧的游戏，所要预判的不是一项投资在长期多年中的未来收益，而是几个月后惯例性估值的基础会是什么；它甚至不需要公众中有“冤大头”来供职业人士吞食——职业人士彼此之间就可以把这场游戏玩下去。也不必有人真的对这种惯例性估值基础具有任何真正的长期有效性抱有朴素信念。因为，说到底，这就像一种 Snap、Old Maid、Musical Chairs 的游戏——谁既不太早也不太晚地喊出 Snap，谁在游戏结束前把 Old Maid递给旁边的人，谁在音乐停止时为自己抢到一把椅子，谁就是赢家。所有玩家明知在流转的是那张 Old Maid，也明知音乐一停，总会有人没有椅子可坐，但这些游戏仍然可以玩得兴致勃勃、乐在其中。

Or, to change the metaphor slightly, professional investment may be likened to those newspaper competitions in which the competitors have to pick out the six prettiest faces from a hundred photographs, the prize being awarded to the competitor whose choice most nearly corresponds to the average preferences of the competitors as a whole; so that each competitor has to pick, not those faces which he himself finds prettiest, but those which he thinks likeliest to catch the fancy of the other competitors, all of whom are looking at the problem from the same point of view. It is not a case of choosing those which, to the best of one's judgment, are really the prettiest, nor even those which average opinion genuinely thinks the prettiest. We have reached the third degree where we devote our intelligences to anticipating what average opinion expects the average opinion to be. And there are some, I believe, who practise the fourth, fifth and higher degrees.

或者，稍微换一个比喻，职业投资可以类比为报纸上的那种竞赛：参赛者要从一百张照片中选出六张最漂亮的脸，奖品颁给那个选择最接近全体参赛者平均偏好的人。因此，每个参赛者要选的，不是自己认为最漂亮的脸，而是他认为最有可能讨其他参赛者喜欢的脸，而所有人都在用同一种视角看这个问题。这不是在挑选那些依自己最佳判断真正最漂亮的，也不是在挑选那些平均意见真心认为最漂亮的。我们已经进入了第三层：把自己的智力用来预判“平均意见所预期的平均意见会是什么”。而且我相信，还有一些人在进行第四层、第五层，乃至更高层次的这种游戏。

If the reader interjects that there must surely be large profits to be gained from the other players in the long run by a skilled individual who, unperturbed by the prevailing pastime, continues to purchase investments on the best genuine long-term expectations he can frame, he must be answered, first of all, that there are, indeed, such serious-minded individuals and that it makes a vast difference to an investment market whether or not they predominate in their influence over the game-players. But we must also add that there are several factors which jeopardise the predominance of such individuals in modern investment markets. Investment based on genuine long-term expectation is so difficult to-day as to be scarcely practicable. He who attempts it must surely lead much more laborious days and run greater risks than he who tries to guess better than the crowd how thc crowd will behave; and, given equal intelligence, he may make more disastrous mistakes. There is no clear evidence from experience that the investment policy which is socially advantageous coincides with that which is most profitable. It needs more intelligence to defeat the forces of time and our ignorance of the future than to beat the gun. Moreover, life is not long enough;¾human nature desires quick results, there is a peculiar zest in making money quickly, and remoter gains are discounted by the average man at a very high rate. The game of professional investment is intolerably boring and over-exacting to anyone who is entirely exempt from the gambling instinct; whilst he who has it must pay to this propensity the appropriate toll. Furthermore, an investor who proposes to ignore near-term market fluctuations needs greater resources for safety and must not operate on so large a scale, if at all, with borrowed money¾a further reason for the higher return from the pastime to a given stock of intelligence and resources. Finally it is the long-term investor, he who most promotes the public interest, who will in practice come in for most criticism, wherever investment funds are managed by committees or boards or banks. For it is in the essence of his behaviour that he should be eccentric, unconventional and rash in the eyes of average opinion. If he is successful, that will only confirm the general belief in his rashness; and if in the short run he is unsuccessful, which is very likely, he will not receive much mercy. Worldly wisdom teaches that it is better for reputation to fail conventionally than to succeed unconventionally.

如果读者插一句说：一个真正有能力的人，如果不受这种流行游戏的干扰，而是继续按照自己所能建立的最佳、真实的长期预期去买入投资，那么从长期看，他当然应该能够从其他玩家那里赚到丰厚利润——对此，首先必须回答：的确存在这样一些严肃认真的人，而且他们在整个游戏中是否占据主导影响力，对一个投资市场来说差别极大。但还必须补充的是，在现代投资市场中，有若干因素会危及这类人的主导地位。建立在真实长期预期基础上的投资，如今困难到几乎无法实行。试图这样做的人，日子一定会过得艰苦得多，承担的风险也会更大；而相比之下，那些只是在猜测大众会怎样行动，并力图比大众更早一步猜中的人，处境要轻松得多。在智力相同的条件下，前者甚至可能犯下更具灾难性的错误。经验并没有清楚证明：社会上更有利的投资政策，恰好也是最赚钱的投资政策。要战胜时间以及我们对未来的无知，比“抢跑”更需要智力。除此之外，人生并不够长——人性追求快结果，快速赚钱有一种特殊的刺激感，而较远期的收益，在普通人那里会被以极高的折现率打折。职业投资这场游戏，对任何完全没有赌博本能的人来说，都无聊得难以忍受，而且要求过高；而有这种本能的人，则必须为这种倾向支付相应代价。再者，一个打算忽略短期市场波动的投资者，需要更雄厚的安全资源，而且不能——即便能，也不该——在很大规模上使用借来的钱操作；这也是为什么在既定的智力和资源存量下，这种“游戏式操作”的回报更高。最后，真正的长期投资者——也就是最能促进公共利益的人——在现实中反而最容易受到指责，尤其是在投资资金由委员会、董事会或银行管理的地方。因为他的行为本质上，在平均意见看来，就是古怪、非传统而且鲁莽。如果他成功了，也只会强化大众关于他“鲁莽”的一般看法；而如果他在短期内失败了——这很可能发生——他则不会得到多少宽容。世俗智慧告诉我们：为了名声，按惯例失败，比以非惯例方式成功更好。

(5) So far we have had chiefly in mind the state of confidence of the speculator or speculative investor himself and may have seemed to be tacitly assuming that, if he himself is satisfied with the prospects, he has unlimited command over money at the market rate of interest. This is, of course, not the case. Thus we must also take account of the other facet of the state of confidence, namely, the confidence of the lending institutions towards those who seek to borrow from them, sometimes described as the state of credit. A collapse in the price of equities, which has had disastrous reactions on the marginal efficiency of capital, may have been due to the weakening either of speculative confidence or of the state of credit. But whereas the weakening of either is enough to cause a collapse, recovery requires the revival of both. For whilst the weakening of credit is sufficient to bring about a collapse, its strengthening, though a necessary condition of recovery, is not a sufficient condition.

到目前为止，我们主要考虑的是投机者或投机性投资者自身的信心状态，因此似乎是在默认这样一种前提：只要他本人对前景满意，他就可以按市场利率无限制地支配资金。当然，事实并非如此。因此，我们还必须考虑信心状态的另一面，也就是放贷机构对那些向它们借款者的信心，这有时被称为信用状态。股票价格的崩溃——并且这种崩溃会对资本边际效率产生灾难性影响——可能源于投机信心的减弱，也可能源于信用状态的减弱。但问题在于，这两者中任何一个的减弱，都足以引发崩溃；而要实现复苏，却必须两者都恢复。因为信用的削弱足以带来崩溃，但信用的增强虽然是复苏的必要条件，却并不是充分条件。

These tendencies are a scarcely avoidable outcome of our having successfully organised 'liquid' investment markets. It is usually agreed that casinos should, in the public interest, be inaccessible and expensive. And perhaps the same is true of stock exchanges. That the sins of the London Stock Exchange are less than those of Wall Street may be due, not so much to differences in national character, as to the fact that to the average Englishman Throgmorton Street is, compared with Wall Street to the average American, inaccessible and very expensive. The jobber's 'turn', the high brokerage charges and the heavy transfer tax payable to the Exchequer, which attend dealings on the London Stock Exchange, sufficiently diminish the liquidity of the market (although the practice of fortnightly accounts operates the other way) to rule out a large proportion of the transactions characteristic of Wall Street. The introduction of a substantial government transfer tax on all transactions might prove the most serviceable reform available, with a view to mitigating the predominance of speculation over enterprise in the United States.

这些倾向，几乎是我们成功构建"流动性"投资市场这一事实所无从回避的结果。人们通常同意，出于公共利益，赌场应当设置较高门槛、让人难以轻易进入且代价高昂。或许股票交易所也应如此。London Stock Exchange 的"罪孽"之所以少于 Wall Street，与其说是源于两国国民性格的差异，不如说是因为：对普通英国人而言，Throgmorton Street 与 Wall Street 对普通美国人相比，进入更为不便，代价也更为高昂。在 London Stock Exchange 进行交易时所涉及的做市商"差价"（jobber's turn）、高额经纪佣金，以及需缴纳国库的沉重印花税，已足以大幅削减市场的流动性（尽管两周一轧账的惯例反向对冲了部分效果），从而将很大一部分在 Wall Street 惯见的交易行为排除在外。对所有交易课征一种实质性的政府转让税，或许能成为现有改革手段中最为有效的一项，以期在美国遏制投机对实业的主导优势。

The spectacle of modern investment markets has sometimes moved me towards the conclusion that to make the purchase of an investment permanent and indissoluble, like marriage, except by reason of death or other grave cause, might be a useful remedy for our contemporary evils. For this would force the investor to direct his mind to the long-term prospects and to those only. But a little consideration of this expedient brings us up against a dilemma, and shows us how the liquidity of investment markets often facilitates, though it sometimes impedes, the course of new investment. For the fact that each individual investor flatters himself that his commitment is 'liquid' (though this cannot be true for all investors collectively) calms his nerves and makes him much more willing to run a risk. If individual purchases of investments were rendered illiquid, this might seriously impede new investment, so long as alternative ways in which to hold his savings are available to the individual. This is the dilemma. So long as it is open to the individual to employ his wealth in hoarding or lending money, the alternative of purchasing actual capital assets cannot be rendered sufficiently attractive (especially to the man who does not manage the capital assets and knows very little about them), except by organising markets wherein these assets can be easily realised for money.

现代投资市场的种种景象有时令我倾向于这样一个结论：若能将投资的购入变得永久且不可撤销——一如婚姻，除非死亡或其他重大原因方可解除——或许将是医治我们当代弊病的一剂良方。因为这将迫使投资者把心思专注于长远前景，且只着眼于此。然而，对这一方案稍加思考，便会遭遇一个两难困境，并让我们看到：投资市场的流动性，往往促进了新投资的进程，尽管有时也会阻碍它。原因在于：每一位投资者都暗自相信自己的持仓是"流动的"（尽管就全体投资者而言，这不可能同时为真），这种幻觉能够平抚其神经，使其更愿意承担风险。若个人的投资购入被迫变为非流动性资产，则在个人仍有其他方式储藏储蓄的情况下，新投资将可能遭受严重阻碍。这便是两难所在。只要个人仍可将其财富用于囤积货币或借贷放款，购买实体资本资产这一替代选择便无法变得足够有吸引力（尤其对于那些并不亲自管理资产、对其知之甚少的人而言），除非通过组建市场，使这些资产能够便利地变现为货币。

The only radical cure for the crises of confidence which afflict the economic life of the modern world would be to allow the individual no choice between consuming his income and ordering the production of the specific capital-asset which, even though it be on precarious evidence, impresses him as the most promising investment available to him. It might be that, at times when he was more than usually assailed by doubts concerning the future, he would turn in his perplexity towards more consumption and less new investment. But that would avoid the disastrous, cumulative and far-reaching repercussions of its being open to him, when thus assailed by doubts, to spend his income neither on the one nor on the other.

对现代世界经济生活中屡屡爆发的信心危机，唯一的根治之法，或许是：让个人别无选择，只能在"消费其收入"与"订购某种特定资本资产的生产"之间二选其一——哪怕这种判断仅凭并不牢靠的证据，也足以使他认为该资产是当下最有前途的投资。诚然，当他比平时更强烈地被对未来的疑虑所困扰时，他或许会在茫然中转向更多消费、更少新投资。但这至少能避免一种更为灾难性的、累积性的、影响深远的后果——即当他被这种疑虑攫住时，他竟选择既不消费、也不投资，将收入悬置于两者之间。

Those who have emphasised the social dangers of the hoarding of money have, of course, had something similar to the above in mind. But they have overlooked the possibility that the phenomenon can occur without any change, or at least any commensurate change, in the hoarding of money.

那些一再强调货币囤积所具有的社会危险性的人，心中当然也抱有与上述类似的想法。但他们忽视了这样一种可能性：这一现象完全可以在货币囤积没有任何变化、或至少没有相应变化的情况下照样发生。

Even apart from the instability due to speculation, there is the instability due to the characteristic of human nature that a large proportion of our positive activities depend on spontaneous optimism rather than on a mathematical expectation, whether moral or hedonistic or economic. Most, probably, of our decisions to do something positive, the full consequences of which will be drawn out over many days to come, can only be taken as a result of animal spirits¾of a spontaneous urge to action rather than inaction, and not as the outcome of a weighted average of quantitative benefits multiplied by quantitative probabilities. Enterprise only pretends to itself to be mainly actuated by the statements in its own prospectus, however candid and sincere. Only a little more than an expedition to the South Pole, is it based on an exact calculation of benefits to come. Thus if the animal spirits are dimmed and the spontaneous optimism falters, leaving us to depend on nothing but a mathematical expectation, enterprise will fade and die;¾though fears of loss may have a basis no more reasonable than hopes of profit had before.

除了投机所引发的不稳定之外，还存在另一种根植于人类本性的不稳定：我们大量积极行动，所依赖的与其说是道德上、享乐上抑或经济上的数学期望值，不如说是一种自发的乐观精神。我们大多数决定采取某种积极行动的决策——其全部后果将在此后许多年里逐步显现——往往只能源于"动物精神"，即一种自发的行动冲动而非不作为的冲动，而非量化收益与量化概率相乘后加权平均的结果。实业界不过是自欺欺人地相信，自己的行动主要受其招股说明书上那些陈述的驱动，无论那些陈述多么坦诚、多么真心。它所依赖的精确收益计算，比起一支奔赴南极的探险队，也多不了多少。因此，一旦动物精神黯淡下去、自发的乐观精神开始动摇，只剩下数学期望值可以依凭，实业便会逐渐萎缩乃至死亡——尽管对亏损的恐惧，其合理性未必比此前对盈利的希望更高。

It is safe to say that enterprise which depends on hopes stretching into the future benefits the community as a whole. But individual initiative will only be adequate when reasonable calculation is supplemented and supported by animal spirits, so that the thought of ultimate loss which often overtakes pioneers, as experience undoubtedly tells us and them, is put aside as a healthy man puts aside the expectation of death.

可以肯定地说，那种寄望于未来、依托希望而推进的实业，总体上有益于整个社会。然而，个人的主动进取只有在理性计算得到"动物精神"的补充与支撑时，才能充分发挥作用——唯有如此，开拓者们时常遭遇的最终亏损的念头（经验毫无疑问地告诉了我们，也告诉了他们这一点），才会被搁置一旁，正如一个健康的人将死亡的念头搁置一旁那样。

This means, unfortunately, not only that slumps and depressions are exaggerated in degree, but that economic prosperity is excessively dependent on a political and social atmosphere which is congenial to the average business man. If the fear of a Labour Government or a New Deal depresses enterprise, this need not be the result either of a reasonable calculation or of a plot with political intent;¾it is the mere consequence of upsetting the delicate balance of spontaneous optimism. In estimating the prospects of investment, we must have regard, therefore, to the nerves and hysteria and even the digestions and reactions to the weather of those upon whose spontaneous activity it largely depends.

不幸的是，这意味着：不仅经济衰退与萧条在程度上会被过度放大，而且经济繁荣也过分依赖于一种令普通商人感到舒适的政治与社会氛围。如果对工党政府或"新政"的恐惧压抑了实业精神，这未必出于任何理性计算，也未必出于任何蓄意的政治阴谋——它不过是打破了那种脆弱的自发乐观平衡的必然后果。因此，在评估投资前景时，我们不得不考虑那些其自发活动在很大程度上支撑着投资的人们的神经状态、情绪起伏，乃至他们的消化状况和对天气变化的反应。

We should not conclude from this that everything depends on waves of irrational psychology. On the contrary, the state of long-term expectation is often steady, and, even when it is not, the other factors exert their compensating effects. We are merely reminding ourselves that human decisions affecting the future, whether personal or political or economic, cannot depend on strict mathematical expectation, since the basis for making such calculations does not exist; and that it is our innate urge to activity which makes the wheels go round, our rational selves choosing between the alternatives as best we are able, calculating where we can, but often falling back for our motive on whim or sentiment or chance.

然而，我们不应由此得出"一切皆取决于非理性心理浪潮"的结论。恰恰相反，长期预期的状态往往是稳定的；即便并非如此，其他因素也会发挥其补偿作用。我们不过是在提醒自己：无论是个人的、政治的还是经济的，凡涉及未来的人类决策，都无法依赖严格的数学期望值——因为作出此类计算的基础本就不存在。推动车轮转动的，是我们与生俱来的行动冲动；我们理性的自我竭尽所能地在各种选项之间做出选择，在能够计算之处进行计算，但往往最终还是将一时的念头、情感或偶然因素作为行动的动因。

There are, moreover, certain important factors which somewhat mitigate in practice the effects of our ignorance of the future. Owing to the operation of compound interest combined with the likelihood of obsolescence with the passage of time, there are many individual investments of which the prospective yield is legitimately dominated by the returns of the comparatively near future. In the case of the most important class of very long-term investments, namely buildings, the risk can be frequently transferred from the investor to the occupier, or at least shared between them, by means of long-term contracts, the risk being outweighed in the mind of the occupier by the advantages of continuity and security of tenure. In the case of another important class of long-term investments, namely public utilities, a substantial proportion of the prospective yield is practically guaranteed by monopoly privileges coupled with the right to charge such rates as will provide a certain stipulated margin. Finally there is a growing class of investments entered upon by, or at the risk of; public authorities, which are frankly influenced in making the investment by a general presumption of there being prospective social advantages from the investment, whatever its commercial yield may prove to be within a wide range, and without seeking to be satisfied that the mathematical expectation of the yield is at least equal to the current rate of interest,¾though the rate which the public authority has to pay may still play a decisive part in determining the scale of investment operations which it can afford.

然而，在实践中，有若干重要因素能够在一定程度上缓解我们对未来无知所带来的影响。由于复利效应的作用，加之资产随时间推移而趋于过时的可能性，许多个别投资的预期收益，在很大程度上合理地取决于相对近期的回报。就最重要的一类超长期投资——即房屋建筑而言，风险往往可以通过长期合同从投资者转移给使用者，或至少由双方共同分担；而在使用者心目中，持续使用与安全租约所带来的好处，足以抵消这种风险。就另一类重要的长期投资——即公用事业而言，其预期收益中相当大的比例，实际上已由垄断特权加上收取足以保证特定利润空间之费率的权利所担保。最后，还有一类日益增长的投资，由公共当局主导或由其承担风险；这类投资在决策时，坦率地受到一种普遍预设的影响，即认为该投资具有前瞻性的社会效益——无论其商业回报在一个宽泛的范围内最终证明为何，也不寻求确认预期收益的数学期望值至少等于当前利率——尽管公共当局所须支付的利率，仍可能在决定其所能负担的投资规模方面发挥举足轻重的作用。

Thus after giving full weight to the importance of the influence of short-period changes in the state of long-term expectation as distinct from changes in the rate of interest, we are still entitled to return to the latter as exercising, at any rate, in normal circumstances, a great, though not a decisive, influence on the rate of investment. Only experience, however, can show how far management of the rate of interest is capable of continuously stimulating the appropriate volume of investment.

因此，在充分考量短期内长期预期状态变化（有别于利率变化）对投资的影响之后，我们仍有理由回到利率本身——它在正常情况下，对投资率施加着重大的、尽管并非决定性的影响。然而，唯有经验才能告诉我们：对利率的管理，究竟能在多大程度上持续地刺激适当规模的投资。

For my own part I am now somewhat sceptical of the success of a merely monetary policy directed towards influencing the rate of interest. I expect to see the State, which is in a position to calculate the marginal efficiency of capital-goods on long views and on the basis of the general social advantage, taking an ever greater responsibility for directly organising investment; since it seems likely that the fluctuations in the market estimation of the marginal efficiency of different types of capital, calculated on the principles I have described above, will be too great to be offset by any practicable changes in the rate of interest.

就我个人而言，我对于单纯以影响利率为目标的货币政策能否奏效，如今已颇为怀疑。我期望看到国家——它有能力从长远角度并基于总体社会效益来计算资本品的边际效率——承担起直接组织投资的更大责任；因为按照我上文所描述的原则计算，市场对不同类型资本边际效率的估算所产生的波动，很可能过于剧烈，以至于任何切实可行的利率调整都无法将其抵消。