顶尖的医生，能从几段病理切片，就窥见患者的病根何在。同样，顶尖的思想家，能通过几篇简单的文章或者演讲，就能洞察时代的弊病。

20世纪是人类历史上灾难最深重的时代，关于20世纪的反思，也是不胜枚举，但是只有极少的思想家，能像哈耶克那样，真正洞悉到20世纪灾难的根源。

1974年，哈耶克荣获诺奖，并发表题为“知识的僭妄” （Pretence），这篇演讲的重大意义在于，他指出了20世纪重大的历史灾难，源于人类试图掌握“社会总规律”的知识野心——将科学方法论被滥用于治理人类社会。

▎诺奖经济学奖没有存在的必要

这篇演讲的特殊场合，再加上我们所面临的实际问题，使我几乎无可避免地选择了这个题目。

一方面，不久前刚刚设立的诺贝尔经济学奖，标志着一个过程又向前迈出了重要的一步，经济学已经赢得了类似于物理学的威望。

另一方面，人们正在呼吁经济学家出来谈一下，如何才能使自由世界摆脱不断加剧的通货膨胀这种严重的威胁。

然而，正是大多数经济学家曾经推荐甚至极力促使政府采取的政策，造成了这种局面。

在我看来，经济学家在指导政策方面没有做得更为成功，同他们总想尽可能严格地效仿成就辉煌的物理学这种嗜好大有关系。

今天我首先想解释一下，这种唯科学主义的谬误，如何直接导致了最近的经济政策中一些最严重的错误。

我曾与之论战的理论，是一种有关正确的科学方法的错误观念的产物，但是在过去30年里，它一直指导着货币和财政政策。

但是我认为，它从根本上就是错误的，我们现在也已经知道，照这样的理论采取行动是十分有害的。

这使我提出了一个关键性问题。与物理学的情况不同，市场是一种十分复杂的现象，它取决于众多个人的行为，对决定着一个过程之结果的所有情况，几乎永远不可能进行充分的了解或计算。

但人们常常十分幼稚地认为，这样的观点是科学工作所必需的，但它却引起了一些荒谬的后果。我们当然知道，在谈论市场和类似的社会结构时，有许许多多的事实是我们无法计算的，对于它们，我们仅仅具有很不精确的一般知识。

他们经常生出一种十分惬意的幻觉：他们能够进行计算的因素，才是唯一相关的因素。

例如，总需求与总就业之间可能仅仅有着“大约的相关性”，但这是我们能够得到量化证据的唯一关系，于是它便成了进行计算的唯一的因果关系。

以此为标准，有可能存在着助长错误理论的更“科学的”证据，因为它比正确的解释更“科学”而被接受，至于正确的解释，却因为不具备足够的量化数据而被否定了。

▎大萧条的元凶不是资本，而是权力

大萧条，是这个时代的痛点。

在我看来，对此正确的解释是，在不同商品和服务的需求分布与这些产出的生产中劳动力和其他资源的配置之间，存在着不一致。

失业表明相对价格和工资结构受到了扭曲（通常是因为垄断或政府的价格锁定），为了在所有部门恢复劳动力的供需平衡，有必要改变相对价格和转移一部分劳动力。

对失业原因的种种解释，是一种经验理论——例如，如果货币供应持续不断，普遍增加工资就不会导致失业；但它肯定无法使我们得出有关工资率、劳动力分布的具体量化预测的理论。

但是，在经济学领域，我们为什么必须为人类对某些事物的无知做出解释呢？

要知道，在自然科学中，人们肯定会期待科学家提供有关这种事实的准确知识。对自然科学的范例有所体验的人，会对这种立场十分不满，他们会坚持自己在自然科学中形成的“证实原则”，这也许不足为奇。

这种状况的原因在于我已简单说过的一个事实：社会科学同生物学差不多，但和大多数自然科学不同，它要处理的是性质复杂的结构，也就是说，它所处理的结构，只能用“包含着较多变量的模式”加以说明。

以竞争过程为例，只有当它在相当多的行动的个人之间进行时，才会产生一定的结果。

我们的理论所要说明的，是在一个功能良好的市场中自发形成的决定着相对价格和工资体系的因素，就这一理论而言，以上所言尤其正确。

苏联计划经济

市场过程的每个参与者所拥有的特殊信息，都会对价格和工资的确定产生影响。这方面的全部事实，我们是无法知晓的，因此我们无法测知它对这种秩序的偏离程度，而且我们无法从统计学的角度，对我们的理论——对价格和工资的“均衡”系统的偏离，使某些产品和服务不可能按定价售出——加以检验。

但有一点是肯定的，正是政府的干预，导致了整个经济系统的扭曲，从而加剧了大萧条。

▎信仰科学，是最大的反科学

许多人认为，我对经济学的数学方法一概加以反对。事实上，我认为数学方法大有益处，它使我们可以利用代数方程式，去描述某个模型的一般性质，即使我们对决定其具体面貌的数据一无所知。

没有这种代数方法，我们对市场中不同事件的相互依赖性，就很难窥其全貌。不过这也导致一种幻想，使我们认为可以用这种技术去搞定和预测各种量的数值，于是徒劳地想找出量的常数。

尽管数理经济学的近代奠基人没有这种幻想，这种情况还是发生了。

他们认为，只有可计算的数据才是重要的——这种迷信在经济领域造成实际危害的事例可能为数不多，但目前的通货膨胀和就业问题却是十分严重的一例。

它所造成的后果是，经济学家中有着唯科学主义头脑的大多数人，对很可能对造成广泛失业的真正原因漠不关心，因为它的作用无法用可以直接观察到的、可计量的数据关系加以证实，他们几乎把全副注意力都用在可以计算的表面现象上，由此产生的政策使事情变得更糟。

当然，必须随时准备承认，我认为对失业现象做出了正确解释的理论，是一种内容有局限性的理论，因为对于既定环境中预计必然会出现的事件的性质，它只能让我们做出十分笼统的预测。但是，更为雄心勃勃的理论建构对政策的影响却没有更加走运。

我必须承认，我更喜欢虽不完美但正确的知识，即使它留下许多无法确定和预测的事情，而不是那种貌似精确但很可能错误的知识。表面上遵守公认的科学标准，会给具有简明外表的错误理论带来虚名，但目前的局势说明，这种理论会导致严重的后果。

▎唯科学主义，必然导向灾难

我提到这些眼前重要的实际问题，主要是想说明，一些可能涉及科学、哲学等抽象问题的错误，将会导致严重的后果。

貌似科学的方法其实是最不科学的，我们所能期待科学达到的目标，是有着明确界限的。这意味着，把科学方法无法做到的事情委托给科学，或按照科学原则去进行人为的控制，有可能招致令人悲哀的后果。

近代以来，自然科学的进步当然大大出乎人们的预料，于是，所有人都会以为这种能力可以使我们随心所欲地改造社会。

人类社会，是一种复杂的有机体为主的领域，人类不可能获得主宰事务进程的充分知识。我们不能像工匠打造器皿那样去模铸产品，而是必须像园丁看护花草那样，利用他所掌握的知识，通过提供适宜的环境，养护花草生长的过程。

自然科学的进步使人类情不自禁地觉得，自己的能力正在无止境地增长，“让人眼花缭乱的成功”——诱使人们不但试图主宰我们的自然环境，甚至想主宰我们的人类环境，这就是危险所在。

社会研究者认识到自己的知识有不可逾越的障碍，便应懂得谦虚为怀的道理，不至于再去充当那些极力想控制社会的狂妄之徒的帮凶；这种做法不但会使他成为自己同胞的暴君，并且可以使他成为一种文明——它不是出自哪个头脑的设计，而是通过千千万万个人的自由努力成长起来——的毁灭者。

Friedrich von Hayek

Prize Lecture

Lecture to the memory of Alfred Nobel, December 11, 1974

The Pretence of Knowledge

The particular occasion of this lecture, combined with the chief practical problem which economists have to face today, have made the choice of its topic almost inevitable. On the one hand the still recent establishment of the Nobel Memorial Prize in Economic Science marks a significant step in the process by which, in the opinion of the general public, economics has been conceded some of the dignity and prestige of the physical sciences. On the other hand, the economists are at this moment called upon to say how to extricate the free world from the serious threat of accelerating inflation which, it must be admitted, has been brought about by policies which the majority of economists recommended and even urged governments to pursue. We have indeed at the moment little cause for pride：as a profession we have made a mess of things.

It seems to me that this failure of the economists to guide policy more successfully is closely connected with their propensity to imitate as closely as possible the procedures of the brilliantly successful physical sciences – an attempt which in our field may lead to outright error. It is an approach which has come to be described as the “scientistic” attitude – an attitude which, as I defined it some thirty years ago, “is decidedly unscientific in the true sense of the word, since it involves a mechanical and uncritical application of habits of thought to fields different from those in which they have been formed.”¹ I want today to begin by explaining how some of the gravest errors of recent economic policy are a direct consequence of this scientistic error.

The theory which has been guiding monetary and financial policy during the last thirty years, and which I contend is largely the product of such a mistaken conception of the proper scientific procedure, consists in the assertion that there exists a simple positive correlation between total employment and the size of the aggregate demand for goods and services; it leads to the belief that we can permanently assure full employment by maintaining total money expenditure at an appropriate level. Among the various theories advanced to account for extensive unemployment, this is probably the only one in support of which strong quantitative evidence can be adduced. I nevertheless regard it as fundamentally false, and to act upon it, as we now experience, as very harmful.

This brings me to the crucial issue. Unlike the position that exists in the physical sciences, in economics and other disciplines that deal with essentially complex phenomena, the aspects of the events to be accounted for about which we can get quantitative data are necessarily limited and may not include the important ones. While in the physical sciences it is generally assumed, probably with good reason, that any important factor which determines the observed events will itself be directly observable and measurable, in the study of such complex phenomena as the market, which depend on the actions of many individuals, all the circumstances which will determine the outcome of a process, for reasons which I shall explain later, will hardly ever be fully known or measurable. And while in the physical sciences the investigator will be able to measure what, on the basis of a prima facie theory, he thinks important, in the social sciences often that is treated as important which happens to be accessible to measurement. This is sometimes carried to the point where it is demanded that our theories must be formulated in such terms that they refer only to measurable magnitudes.

It can hardly be denied that such a demand quite arbitrarily limits the facts which are to be admitted as possible causes of the events which occur in the real world. This view, which is often quite naively accepted as required by scientific procedure, has some rather paradoxical consequences. We know：of course, with regard to the market and similar social structures, a great many facts which we cannot measure and on which indeed we have only some very imprecise and general information. And because the effects of these facts in any particular instance cannot be confirmed by quantitative evidence, they are simply disregarded by those sworn to admit only what they regard as scientific evidence：they thereupon happily proceed on the fiction that the factors which they can measure are the only ones that are relevant.

The correlation between aggregate demand and total employment, for instance, may only be approximate, but as it is the only one on which we have quantitative data, it is accepted as the only causal connection that counts. On this standard there may thus well exist better “scientific” evidence for a false theory, which will be accepted because it is more “scientific”, than for a valid explanation, which is rejected because there is no sufficient quantitative evidence for it.

Let me illustrate this by a brief sketch of what I regard as the chief actual cause of extensive unemployment – an account which will also explain why such unemployment cannot be lastingly cured by the inflationary policies recommended by the now fashionable theory. This correct explanation appears to me to be the existence of discrepancies between the distribution of demand among the different goods and services and the allocation of labour and other resources among the production of those outputs. We possess a fairly good “qualitative” knowledge of the forces by which a correspondence between demand and supply in the different sectors of the economic system is brought about, of the conditions under which it will be achieved, and of the factors likely to prevent such an adjustment. The separate steps in the account of this process rely on facts of everyday experience, and few who take the trouble to follow the argument will question the validity of the factual assumptions, or the logical correctness of the conclusions drawn from them. We have indeed good reason to believe that unemployment indicates that the structure of relative prices and wages has been distorted（usually by monopolistic or governmental price fixing）, and that to restore equality between the demand and the supply of labour in all sectors changes of relative prices and some transfers of labour will be necessary.

But when we are asked for quantitative evidence for the particular structure of prices and wages that would be required in order to assure a smooth continuous sale of the products and services offered, we must admit that we have no such information. We know, in other words, the general conditions in which what we call, somewhat misleadingly, an equilibrium will establish itself：but we never know what the particular prices or wages are which would exist if the market were to bring about such an equilibrium. We can merely say what the conditions are in which we can expect the market to establish prices and wages at which demand will equal supply. But we can never produce statistical information which would show how much the prevailing prices and wages deviate from those which would secure a continuous sale of the current supply of labour. Though this account of the causes of unemployment is an empirical theory, in the sense that it might be proved false, e.g. if, with a constant money supply, a general increase of wages did not lead to unemployment, it is certainly not the kind of theory which we could use to obtain specific numerical predictions concerning the rates of wages, or the distribution of labour, to be expected.

Why should we, however, in economics, have to plead ignorance of the sort of facts on which, in the case of a physical theory, a scientist would certainly be expected to give precise information? It is probably not surprising that those impressed by the example of the physical sciences should find this position very unsatisfactory and should insist on the standards of proof which they find there. The reason for this state of affairs is the fact, to which I have already briefly referred, that the social sciences, like much of biology but unlike most fields of the physical sciences, have to deal with structures of essential complexity, i.e. with structures whose characteristic properties can be exhibited only by models made up of relatively large numbers of variables. Competition, for instance, is a process which will produce certain results only if it proceeds among a fairly large number of acting persons.

In some fields, particularly where problems of a similar kind arise in the physical sciences, the difficulties can be overcome by using, instead of specific information about the individual elements, data about the relative frequency, or the probability, of the occurrence of the various distinctive properties of the elements. But this is true only where we have to deal with what has been called by Dr. Warren Weaver（formerly of the Rockefeller Foundation）, with a distinction which ought to be much more widely understood, “phenomena of unorganized complexity,” in contrast to those “phenomena of organized complexity” with which we have to deal in the social sciences.² Organized complexity here means that the character of the structures showing it depends not only on the properties of the individual elements of which they are composed, and the relative frequency with which they occur, but also on the manner in which the individual elements are connected with each other. In the explanation of the working of such structures we can for this reason not replace the information about the individual elements by statistical information, but require full information about each element if from our theory we are to derive specific predictions about individual events. Without such specific information about the individual elements we shall be confined to what on another occasion I have called mere pattern predictions – predictions of some of the general attributes of the structures that will form themselves, but not containing specific statements about the individual elements of which the structures will be made up.³

This is particularly true of our theories accounting for the determination of the systems of relative prices and wages that will form themselves on a well functioning market. Into the determination of these prices and wages there will enter the effects of particular information possessed by every one of the participants in the market process – a sum of facts which in their totality cannot be known to the scientific observer, or to any other single brain. It is indeed the source of the superiority of the market order, and the reason why, when it is not suppressed by the powers of government, it regularly displaces other types of order, that in the resulting allocation of resources more of the knowledge of particular facts will be utilized which exists only dispersed among uncounted persons, than any one person can possess. But because we, the observing scientists, can thus never know all the determinants of such an order, and in consequence also cannot know at which particular structure of prices and wages demand would everywhere equal supply, we also cannot measure the deviations from that order; nor can we statistically test our theory that it is the deviations from that “equilibrium” system of prices and wages which make it impossible to sell some of the products and services at the prices at which they are offered.

Before I continue with my immediate concern, the effects of all this on the employment policies currently pursued, allow me to define more specifically the inherent limitations of our numerical knowledge which are so often overlooked. I want to do this to avoid giving the impression that I generally reject the mathematical method in economics. I regard it in fact as the great advantage of the mathematical technique that it allows us to describe, by means of algebraic equations, the general character of a pattern even where we are ignorant of the numerical values which will determine its particular manifestation. We could scarcely have achieved that comprehensive picture of the mutual interdependencies of the different events in a market without this algebraic technique. It has led to the illusion, however, that we can use this technique for the determination and prediction of the numerical values of those magnitudes; and this has led to a vain search for quantitative or numerical constants. This happened in spite of the fact that the modern founders of mathematical economics had no such illusions. It is true that their systems of equations describing the pattern of a market equilibrium are so framed that if we were able to fill in all the blanks of the abstract formulae, i.e. if we knew all the parameters of these equations, we could calculate the prices and quantities of all commodities and services sold. But, as Vilfredo Pareto, one of the founders of this theory, clearly stated, its purpose cannot be “to arrive at a numerical calculation of prices”, because, as he said, it would be “absurd” to assume that we could ascertain all the data.⁴ Indeed, the chief point was already seen by those remarkable anticipators of modern economics, the Spanish schoolmen of the sixteenth century, who emphasized that what they called pretium mathematicum, the mathematical price, depended on so many particular circumstances that it could never be known to man but was known only to God.⁵ I sometimes wish that our mathematical economists would take this to heart. I must confess that I still doubt whether their search for measurable magnitudes has made significant contributions to our theoretical understanding of economic phenomena – as distinct from their value as a description of particular situations. Nor am I prepared to accept the excuse that this branch of research is still very young：Sir William Petty, the founder of econometrics, was after all a somewhat senior colleague of Sir Isaac Newton in the Royal Society!

There may be few instances in which the superstition that only measurable magnitudes can be important has done positive harm in the economic field：but the present inflation and employment problems are a very serious one. Its effect has been that what is probably the true cause of extensive unemployment has been disregarded by the scientistically minded majority of economists, because its operation could not be confirmed by directly observable relations between measurable magnitudes, and that an almost exclusive concentration on quantitatively measurable surface phenomena has produced a policy which has made matters worse.

It has, of course, to be readily admitted that the kind of theory which I regard as the true explanation of unemployment is a theory of somewhat limited content because it allows us to make only very general predictions of the kind of events which we must expect in a given situation. But the effects on policy of the more ambitious constructions have not been very fortunate and I confess that I prefer true but imperfect knowledge, even if it leaves much undetermined and unpredictable, to a pretence of exact knowledge that is likely to be false. The credit which the apparent conformity with recognized scientific standards can gain for seemingly simple but false theories may, as the present instance shows, have grave consequences.

In fact, in the case discussed, the very measures which the dominant “macro-economic” theory has recommended as a remedy for unemployment, namely the increase of aggregate demand, have become a cause of a very extensive misallocation of resources which is likely to make later large-scale unemployment inevitable. The continuous injection of additional amounts of money at points of the economic system where it creates a temporary demand which must cease when the increase of the quantity of money stops or slows down, together with the expectation of a continuing rise of prices, draws labour and other resources into employments which can last only so long as the increase of the quantity of money continues at the same rate – or perhaps even only so long as it continues to accelerate at a given rate. What this policy has produced is not so much a level of employment that could not have been brought about in other ways, as a distribution of employment which cannot be indefinitely maintained and which after some time can be maintained only by a rate of inflation which would rapidly lead to a disorganisation of all economic activity. The fact is that by a mistaken theoretical view we have been led into a precarious position in which we cannot prevent substantial unemployment from re-appearing; not because, as this view is sometimes misrepresented, this unemployment is deliberately brought about as a means to combat inflation, but because it is now bound to occur as a deeply regrettable but inescapable consequence of the mistaken policies of the past as soon as inflation ceases to accelerate.

I must, however, now leave these problems of immediate practical importance which I have introduced chiefly as an illustration of the momentous consequences that may follow from errors concerning abstract problems of the philosophy of science. There is as much reason to be apprehensive about the long run dangers created in a much wider field by the uncritical acceptance of assertions which have the appearance of being scientific as there is with regard to the problems I have just discussed. What I mainly wanted to bring out by the topical illustration is that certainly in my field, but I believe also generally in the sciences of man, what looks superficially like the most scientific procedure is often the most unscientific, and, beyond this, that in these fields there are definite limits to what we can expect science to achieve. This means that to entrust to science – or to deliberate control according to scientific principles – more than scientific method can achieve may have deplorable effects. The progress of the natural sciences in modern times has of course so much exceeded all expectations that any suggestion that there may be some limits to it is bound to arouse suspicion. Especially all those will resist such an insight who have hoped that our increasing power of prediction and control, generally regarded as the characteristic result of scientific advance, applied to the processes of society, would soon enable us to mould society entirely to our liking. It is indeed true that, in contrast to the exhilaration which the discoveries of the physical sciences tend to produce, the insights which we gain from the study of society more often have a dampening effect on our aspirations; and it is perhaps not surprising that the more impetuous younger members of our profession are not always prepared to accept this. Yet the confidence in the unlimited power of science is only too often based on a false belief that the scientific method consists in the application of a ready-made technique, or in imitating the form rather than the substance of scientific procedure, as if one needed only to follow some cooking recipes to solve all social problems. It sometimes almost seems as if the techniques of science were more easily learnt than the thinking that shows us what the problems are and how to approach them.

The conflict between what in its present mood the public expects science to achieve in satisfaction of popular hopes and what is really in its power is a serious matter because, even if the true scientists should all recognize the limitations of what they can do in the field of human affairs, so long as the public expects more there will always be some who will pretend, and perhaps honestly believe, that they can do more to meet popular demands than is really in their power. It is often difficult enough for the expert, and certainly in many instances impossible for the layman, to distinguish between legitimate and illegitimate claims advanced in the name of science. The enormous publicity recently given by the media to a report pronouncing in the name of science on The Limits to Growth, and the silence of the same media about the devastating criticism this report has received from the competent experts⁶, must make one feel somewhat apprehensive about the use to which the prestige of science can be put. But it is by no means only in the field of economics that far-reaching claims are made on behalf of a more scientific direction of all human activities and the desirability of replacing spontaneous processes by “conscious human control”. If I am not mistaken, psychology, psychiatry and some branches of sociology, not to speak about the so-called philosophy of history, are even more affected by what I have called the scientistic prejudice, and by specious claims of what science can achieve.⁷

If we are to safeguard the reputation of science, and to prevent the arrogation of knowledge based on a superficial similarity of procedure with that of the physical sciences, much effort will have to be directed toward debunking such arrogations, some of which have by now become the vested interests of established university departments. We cannot be grateful enough to such modern philosophers of science as Sir Karl Popper for giving us a test by which we can distinguish between what we may accept as scientific and what not – a test which I am sure some doctrines now widely accepted as scientific would not pass. There are some special problems, however, in connection with those essentially complex phenomena of which social structures are so important an instance, which make me wish to restate in conclusion in more general terms the reasons why in these fields not only are there only absolute obstacles to the prediction of specific events, but why to act as if we possessed scientific knowledge enabling us to transcend them may itself become a serious obstacle to the advance of the human intellect.

The chief point we must remember is that the great and rapid advance of the physical sciences took place in fields where it proved that explanation and prediction could be based on laws which accounted for the observed phenomena as functions of comparatively few variables – either particular facts or relative frequencies of events. This may even be the ultimate reason why we single out these realms as “physical” in contrast to those more highly organized structures which I have here called essentially complex phenomena. There is no reason why the position must be the same in the latter as in the former fields. The difficulties which we encounter in the latter are not, as one might at first suspect, difficulties about formulating theories for the explanation of the observed events – although they cause also special difficulties about testing proposed explanations and therefore about eliminating bad theories. They are due to the chief problem which arises when we apply our theories to any particular situation in the real world. A theory of essentially complex phenomena must refer to a large number of particular facts; and to derive a prediction from it, or to test it, we have to ascertain all these particular facts. Once we succeeded in this there should be no particular difficulty about deriving testable predictions – with the help of modern computers it should be easy enough to insert these data into the appropriate blanks of the theoretical formulae and to derive a prediction. The real difficulty, to the solution of which science has little to contribute, and which is sometimes indeed insoluble, consists in the ascertainment of the particular facts.

A simple example will show the nature of this difficulty. Consider some ball game played by a few people of approximately equal skill. If we knew a few particular facts in addition to our general knowledge of the ability of the individual players, such as their state of attention, their perceptions and the state of their hearts, lungs, muscles etc. at each moment of the game, we could probably predict the outcome. Indeed, if we were familiar both with the game and the teams we should probably have a fairly shrewd idea on what the outcome will depend. But we shall of course not be able to ascertain those facts and in consequence the result of the game will be outside the range of the scientifically predictable, however well we may know what effects particular events would have on the result of the game. This does not mean that we can make no predictions at all about the course of such a game. If we know the rules of the different games we shall, in watching one, very soon know which game is being played and what kinds of actions we can expect and what kind not. But our capacity to predict will be confined to such general characteristics of the events to be expected and not include the capacity of predicting particular individual events.

This corresponds to what I have called earlier the mere pattern predictions to which we are increasingly confined as we penetrate from the realm in which relatively simple laws prevail into the range of phenomena where organized complexity rules. As we advance we find more and more frequently that we can in fact ascertain only some but not all the particular circumstances which determine the outcome of a given process; and in consequence we are able to predict only some but not all the properties of the result we have to expect. Often all that we shall be able to predict will be some abstract characteristic of the pattern that will appear – relations between kinds of elements about which individually we know very little. Yet, as I am anxious to repeat, we will still achieve predictions which can be falsified and which therefore are of empirical significance.

Of course, compared with the precise predictions we have learnt to expect in the physical sciences, this sort of mere pattern predictions is a second best with which one does not like to have to be content. Yet the danger of which I want to warn is precisely the belief that in order to have a claim to be accepted as scientific it is necessary to achieve more. This way lies charlatanism and worse. To act on the belief that we possess the knowledge and the power which enable us to shape the processes of society entirely to our liking, knowledge which in fact we do not possess, is likely to make us do much harm. In the physical sciences there may be little objection to trying to do the impossible; one might even feel that one ought not to discourage the over-confident because their experiments may after all produce some new insights. But in the social field the erroneous belief that the exercise of some power would have beneficial consequences is likely to lead to a new power to coerce other men being conferred on some authority. Even if such power is not in itself bad, its exercise is likely to impede the functioning of those spontaneous ordering forces by which, without understanding them, man is in fact so largely assisted in the pursuit of his aims. We are only beginning to understand on how subtle a communication system the functioning of an advanced industrial society is based – a communications system which we call the market and which turns out to be a more efficient mechanism for digesting dispersed information than any that man has deliberately designed.

If man is not to do more harm than good in his efforts to improve the social order, he will have to learn that in this, as in all other fields where essential complexity of an organized kind prevails, he cannot acquire the full knowledge which would make mastery of the events possible. He will therefore have to use what knowledge he can achieve, not to shape the results as the craftsman shapes his handiwork, but rather to cultivate a growth by providing the appropriate environment, in the manner in which the gardener does this for his plants. There is danger in the exuberant feeling of ever growing power which the advance of the physical sciences has engendered and which tempts man to try, “dizzy with success”, to use a characteristic phrase of early communism, to subject not only our natural but also our human environment to the control of a human will. The recognition of the insuperable limits to his knowledge ought indeed to teach the student of society a lesson of humility which should guard him against becoming an accomplice in men’s fatal striving to control society – a striving which makes him not only a tyrant over his fellows, but which may well make him the destroyer of a civilization which no brain has designed but which has grown from the free efforts of millions of individuals.

1. “Scientism and the Study of Society”, Economica, vol. IX, no. 35, August 1942, reprinted in The Counter-Revolution of Science, Glencoe, Ill., 1952, p. 15 of this reprint.

2. Warren Weaver, “A Quarter Century in the Natural Sciences”, The Rockefeller Foundation Annual Report 1958, chapter I, “Science and Complexity”.

3. See my essay “The Theory of Complex Phenomena” in The Critical Approach to Science and Philosophy. Essays in Honor of K.R. Popper, ed. M. Bunge, New York 1964, and reprinted（with additions）in my Studies in Philosophy, Politics and Economics, London and Chicago 1967.

4. V. Pareto, Manuel d’économie politique, 2nd. ed., Paris 1927, pp. 223-4.

5. See, e.g., Luis Molina, De iustitia et iure, Cologne 1596-1600, tom. II, disp. 347, no. 3, and particularly Johannes de Lugo, Disputationum de iustitia et iure tomus secundus, Lyon 1642, disp. 26, sect. 4, no. 40.

6. See The Limits to Growth：A Report of the Club of Rome’s Project on the Predicament of Mankind, New York 1972; for a systematic examination of this by a competent economist cf. Wilfred Beckerman, In Defence of Economic Growth, London 1974, and, for a list of earlier criticisms by experts, Gottfried Haberler, Economic Growth and Stability, Los Angeles 1974, who rightly calls their effect “devastating”.

7. I have given some illustrations of these tendencies in other fields in my inaugural lecture as Visiting Professor at the University of Salzburg, Die Irrtümer des Konstruktivismus und die Grundlagen legitimer Kritik gesellschaftlicher Gebilde, Munich 1970, now reissued for the Walter Eucken Institute, at Freiburg i.Brg. by J.C.B. Mohr, Tübingen 1975.

From Nobel Lectures, Economics 1969-1980, Editor Assar Lindbeck, World Scientific Publishing Co., Singapore, 1992