(《奎因短文集:一本不拘泥于分类学标准的哲学词典》,译者:翟玉章)
Prediction
预言
【原始预言的基础是作为动物本能的简单归纳:期望相似的经验有相似的后继者。简单归纳中的主观相似性标准。主观相似性标准对客观世界的适应性的进化论解释。假说演绎法对简单归纳的突破。观察直言句:科学理论的最初形式、发达的科学理论与日常世界相联系的桥梁。预言是科学的定义性特征,尽管已不再是科学的主要目的。
本文提到的词条:预言、事物、类与性质。
A prediction may turn out true or false, but either way it is diction: it has to be spoken or, to stretch a point, written. Etymology and the dictionary agree on the point. The near-synonyms 'foresight', 'foreknowledge', and 'precognition' are free of that limitation, but subject to others. Foreknowledge has to be true, indeed infallible. Foresight is limited to the visual when taken etymologically, and is vague otherwise. 'Precognition' connotes clairvoyance.
预言(prediction)可真可假,但不管是真是假,它总与语词有关:它必须用语词说出或写出。词源学和词典在这一点上是一致的。它的近义词“前见”(foresight)、“预知”(foreknowledge)和“先知”(precognition)没有语词上的限制,但有其他限制。预知必须是真的,而且是不可错的。前见从词源上说与视觉有关;至于与视觉无关的前见,含义是含糊的。先知则与特异功能有关。
GOOGLE: A prediction can be true or false, but whether it is true or false, it is always related to words: it must be spoken or written in words. Etymology and lexicon agree on this. Its near-synonyms "foresight", "foreknowledge" and "precognition" have no verbal restriction, but have other restrictions. "Foreknowledge" must be true and infallible. Foresight is etymologically related to vision; as for foresights which have nothing to do with vision, what do they mean is unclear. Precognitions are related to clairvoyance.
'Prediction' remains the usual word for my present topic, and we had best limp along with it. When treating of babies or other dumb animals we can retreat to 'expectation', ignoring its less obtrusive etymology, or to 'anticipation'.
最适合于我当前话题的还是“预言”这个常用词。我们会一直使用这个词,但在谈到婴儿或其他不会说话的动物时,我们将退而使用“期望”(expectation,不考虑它不太显眼的词源)这个词,或“预期”(anticipation)这个词。
GOOGLE:The most appropriate word for my current topic is the common word "prediction." We will always use this word, but when talking about babies or other dumb animals, we will fall back to "expectation" (despite its less obvious etymology), or "anticipation".
Prediction is rooted in a general tendency among higher vertebrates to expect that similar experiences will have sequels similar to each other. Similarity, however, for all its seeming familiarity, is a hard notion to pin down. Can we say that things are more or less similar according as they share more or fewer properties? Well, how many properties are shared by two peas, or by Boston and Philadelphia, or by my brother and me? When it comes to enumerating properties, we don't know where to begin. The notion of a property, for all its seeming familiarity, is as dim a notion as that of similarity.
预言根植于高等脊椎动物的一种普遍倾向,即期望相似的经验有相似的后继者。然而,相似性尽管看上去熟悉,但却难以下定义。事物之间的相似性程度取决于它们共享性质的多寡吗?请问,两粒豌豆有多少共享的性质?波士顿和费城有多少共享的性质?我和我的哥哥又有多少共享的性质?我们还真不知道如何着手列举性质。性质尽管看上去也是熟悉的,但其实和相似性一样地不清楚。
GOOGLE: Prediction is rooted in a common tendency among higher vertebrates to expect similar experiences to have similar sequels. However, similarity, while familiar, is difficult to define. Does the degree of similarity between things depend on the number of properties they share? How many properties do two peas share? How many properties do Boston and Philadelphia share? How many properties do my brother and I share? We don't really know how to go about enumerating properties. Property, although familiar, is in fact as unclear as similarity.
CLASSES, we saw, stand in for properties when there is work to be done. They likewise are of no help, however, in defining {160} similarity. Things cannot be said to be more or less similar according as they are fellow members of more or fewer classes. One pair of things may be expected to be fellow members of just as many classes -- countless, namely -- as another pair.
我们看到,当有工作要做时,类可以代替属性(见类与性质)。但在面对相似性的定义时,类和性质一样无能为力。我们不能说,事物之间的相似性程度的大小取决于它们都属于的类的多寡。任何一对事物所属于的类,与任何另外一对事物所属于的类,是一样多的,即都有无穷多个。
GOOGLE: We saw that CLASSES can replace properties when there is work to be done. But when faced with the definition of similarity, classes are just as helpless as properties. We cannot say that the similarity between things depends on the number of classes to which they all belong. There are as many classes to which any pair of things belong, as there are to any other pair of things, i.e., countless in number.
We see a neat way around the obstacle when we take note of the particular context of similarity that concerns us: the creature's expectation that similar experiences will have similar sequels. What matters is only what counts as subjective similarity of experiences for the creature in question. This, providentially, admits of definition, or testing anyway, even if objective similarity does not.
如果我们注意到我们感兴趣的相似性的特殊背景,我们就可以利用相似的经验有相似的后继者这一普遍的倾向,而巧妙地绕过障碍。真正重要的只是正在讨论的生物的经验对它自己而言的主观相似性。很幸运,这种主观相似性是可以接受定义或检验的,尽管客观的相似性不能。
GOOGLE: If we pay attention to the particular context of the similarity that interest us, we can cleverly bypass obstacles by taking advantage of the general tendency for similar experiences to have similar successors. All that really matters is the subjective similarity of experiences to the creature in question. Fortunately, this subjective similarity can be defined or tested, although objective similarity cannot.
Our own handles on the creature's experiences are the stimulations that engender them. By experimenting in stimulation, reward, and punishment we can compare the stimulations in respect of how similar they are for him. We reward his response to one stimulation and we penalize the same response on the occasion of another stimulation; then we conclude that a third stimulation is more similar to the first for him than to the second if it again evokes the response. There would seldom be profit in doing this, but the point of describing it is to give experimental meaning to the notion of subjective similarity. It was more than we could do for objective or absolute similarity.
我们自己用来控制生物经验的抓手是它们得以产生的刺激。通过对刺激、奖励和惩罚进行实验,我们可以比较各种刺激对该生物的相似性。我们奖励它对一个刺激的反应,惩罚它对另一个刺激的同样反应;然后我们得出结论:如果第三个刺激再次引起同样的反应,那么第三个刺激与第一个刺激比与第二个刺激更相似。这样做很少会有好处,我把它描述出来只是为了赋予主观相似性这一概念以实验意义[1]。相比之下,我们对客观或绝对的相似性则无计可施。
GOOGLE: The grips we use to control a creature's experiences are the stimuli that produce them. By experimenting with stimuli, rewards, and punishments, we can compare the similarity of various stimuli relative to that creature. We reward it for its response to one stimulus and punish it for the same response to another stimulus; then we conclude: If a third stimulus elicits the same response again, then it is more similar to the first than to the second. There is rarely any benefit for doing this, and I describe it only to give experimental significance to the notion of subjective similarity. In contrast, there is nothing we can do about objective or absolute similarity.
In our expectation that subjectively similar events will have similar sequels, we and other animals are often deceived. "Life," in the words of A. E. Housman, "is uncertain. Life, I repeat, is not a stranger to uncertainty." What is uncanny, however, is how overwhelmingly much more often our expectations are fulfilled than disappointed. We take their fulfillment hour in and hour out as a humdrum matter of course; the occasional unexpectedness is what we notice. Our standard of similarity, for all its subjectivity, is remarkably attuned to the course of nature. For all its subjectivity, in short, it is remarkably objective.
我们和其他动物的期望(主观上相似的事件有相似的后继者)经常会落空。“生活,”用A. E. 豪斯曼的话来说,“是不确实的。生活,我再说一遍,对不确实性并不陌生。[2]”但不可思议的是,期望应验的时候远远多于失败的时候。我们对期望的应验已经司空见惯,偶尔的失败才引人注目。我们的相似性标准尽管是主观的,但与自然的进程却非常合拍。换言之,主观的相似性标准从效果上看是非常客观的。
GOOGLE: Our expectations and those of other animals—that subjectively similar events have similar successors—are often frustrated. "Life," in the words of A. E. Hausman, "is uncertain. Life, I repeat, is not free from uncertainty." But the incredible thing is that our expectations are fulfilled far more often than they fail. We have become accustomed to the fulfillment of our expectations; It's the occasional failure that catches the eye. Our standard of similarity, although subjective, is very much in tune with the course of nature. In other words, the subjective standard of similarity is, in effect, very objective.
In the light of Darwin's theory of natural selection we can see why this might be. Veridical expectation has survival value in the wild. Innate standards of subjective similarity that {160} promote successful expectation will tend to be handed down through the survival of the fittest. The tendency will have favored us and other species as well. These considerations offer no promise of future success if nature takes what we would regard as a sudden turn, but they do account plausibly for how well we have been doing up to now.
我们可以用达尔文的自然选择理论来解释我们的期望为什么往往是应验的。应验的期望在原始环境中是有生存价值的。导致期望成功的天生的主观相似性标准会在适者生存的自然选择中被传承下来。我们和其他现存的动物就是这一趋势的受益者。当然,这些考虑并不保证我们的相似性标准在未来仍会管用,因为自然可能会发生我们它在其中不再有效的剧烈变化,但确实合理地解释了它为什么迄今为止是管用的。
GOOGLE: We can use Darwin’s theory of natural selection to explain why our expectations tend to come true. Successful expectations have survival value in primitive environments. Innate subjective standards of similarity that lead to successful expectations are passed down through natural selection based on the survival of the fittest. We and other living animals are beneficiaries of this trend. Of course, these considerations do not guarantee that our similarity standards will still work in the future, since nature may change dramatically enough, but they do provide a reasonable explanation for why they have worked so far.
Such was prediction, or better, expectation, when the jungle law of tooth and claw held sway in man's primordial day. A man sees the dawn's early light and, in the light of past experience, he expects birds to sing. Or, blessed with language, he sees the dawn and says "The birds will sing." This is prediction. In the fullness of time he verbalizes his habitual expectation and says "When the sun comes up the birds sing." This, which I call an observation categorical is the first step in scientific theory. It is a hypothesis that generates predictions and can be refuted by failure of prediction.
在弱肉强食的原始社会,预言(称为期望更恰当)大致是这样的:一个人看到黎明的曙光,然后根据他过去的经验期望鸟儿唱歌。后来,他拥有了语言,便会在看到黎明时说出“鸟儿将唱歌。”这已经是名副其实的预言了。最后,他用语言来表达他司空见惯的期望:“每当太阳升起,鸟儿唱歌。”我把这样的语句称为观察直言句,这是科学理论的最初形式。一个观察直言句是一个可以用来预言的假说;如果它所预言的事情没有发生,它将被驳倒。
In the primitive society where the jungle law prevails, a prediction (more appropriately called expectation) goes like this: a person sees the dawn and then expects the birds to sing based on his past experience. Later, he is given language and would say "The birds will sing" when he sees the dawn. This is prediction. Finally, he uses language to express his commonplace expectation: "Whenever the sun rises, the birds sing." I call such a statement an observation categorical, which is the original form of scientific theories. This is a hypothesis that produces a prediction; if the predicted thing does not happen, it will be refuted.
Such generalization, called simple induction, distinguishes us none from other high mammals except that we verbalize it. It only puts words to their habitual expectations. Sophisticated science far transcends simple induction. It interpolates unseen interim careers of seen things (see THINGS) and fabricates terms for fancied things unseen. It posits abstract objects, notably numbers, and with help of these devises measurement. Thus arises a powerful and virtually conclusive refinement of induction, the method of which John Stuart Mill called concomitant variation. An intricate web of hypotheses is devised which together imply a host of observation categoricals. Such is the "hypothetico-deductive method."
这种被称为简单归纳的概括法,并没有将我们与其他高等哺乳动物区别开来。我们只是会用语言来表达自己的习惯性期望而已。高等科学远远超越了简单归纳法。它往可见的事物中插入不可见的过渡事物(见事物)并为这些设定的事物造出新的术语。它还设定了抽象对象,特别是数,并借助于这些抽象对象制定了测量系统。这样就诞生了定量归纳法。这种经过改进的更加强大的归纳法被约翰·斯图尔特·密尔称为共变法。科学家可以设计出一个错综复杂的、可以联合蕴涵一系列观察直言句的假说网络,这就是假说演绎法。
GOOGLE:This generalization, called simple induction, does not distinguish us from other higher mammals. We just use language to express our habitual expectations. Higher science goes far beyond simple induction. It inserts invisible transitional things into the visible things (see THINGS) and creates new terms for these posited things. It also posits abstract objects, especially numbers, and formulates systems of measurement with the help of these abstract objects. Thus arises the quantitative induction. This improved and more powerful induction was called concomitant variation by John Stuart Mill. Now scientists can devise an intricate network of hypotheses that jointly imply a series of observation categoricals. Such is the “hypothetico-deductive method.”
Science, for all its refinement, does not lose the common touch. The observation categorical is still the touchstone. It says that if the experimental condition is set up, observable by the scientists concerned, then the predicted observation will ensue. If the prediction fails, then the theory, which implied the observation categorical, is refuted. The empirical meaning or content of the theory, we might say, is the set of all implied observation categoricals. In practice of course the links of {162}implication are not explicitly set forth, and many of the contributing hypotheses themselves are commonsense platitudes that one does not stop to state.
科学不管发达到什么地步,都不会完全脱离日常世界。对它的检验仍要归结为对观察直言句的检验。一个观察直言句所说的是:如果有关科学家可以观察到的实验条件被建立了起来,那么被预言的观察结果将随之而出现。如果预言失败了,那么蕴涵这个观察直言句的理论就被驳倒了。我们不妨说,理论的经验意义或经验内容就是它所蕴涵的所有观察直言句。当然,在实践层面上,蕴涵关系的细节并不会一一得到明确的阐明,参与联合蕴涵的许多假说是不言而喻的常识。
GOOGLE: No matter how advanced science is, it will never be completely divorced from everyday world. The test of them still boils down to the test of observation categoricals. An observation categorical says that if the experimental condition, which is observable to the scientists concerned, is established, then the predicted observation will follow. If the prediction fails, then the theory implying the observation categorical is refuted. We might as well say that the empirical meaning or empirical content of a theory is all the observation categoricals it implies. Of course, at a practical level, the details of the implication are not explicitly spelled out one by one, and many of the hypotheses involved in joint implication are common senses which go without saying.
Hypotheses about history, even of the remote past, are part and parcel of science in the inclusive sense, and the arbiter is still prediction. Occasionally this is evident, as when a hypothesis about ancient history implies the findings of some future excavation. More often the historical proposition will link up only very indirectly with prediction, through participating in a large, cohesive section of scholarly and scientific lore and common sense which has its ultimate links with observation categoricals and prediction somewhere outside the historical quarter. But prediction is always the bottom line. It is what gives science its empirical content, its link with nature. It is what makes the difference between science, however high-flown and imaginative, on the one hand, and sheer fancy on the other.
关于历史的假说,即使是关于遥远过去的假说,也是广义上的科学的重要组成部分,对它们的检验手段也仍然是预言。这一点有时是显而易见的:例如,关于古代历史的一个假说蕴涵了未来某个发掘的成果。更常见的情况是,历史主张和预言之间只有非常间接的联系;该主张加入了一个由学术知识、科学知识和常识所组成的庞大而统一的系统,这个系统最终所联系的观察直言句和预言却在历史学的领域之外。但预言始终是底线。它赋予科学以经验内容,并使其与自然相联系。它也是科学(无论多么浮夸和虚构)与纯粹幻想的分水岭。
GOOGLE:Hypotheses about history, even about the distant past, are an important part of science in the broader sense, and prediction still is the test. This is sometimes obvious; for example, when a hypothesis under discussion about ancient history implies the findings in some future excavation. More commonly, there is only a very indirect connection between the historical claim and prediction; it joins a large and unified system of scholarly and scientific knowledge and common sense, and the observation categoricals and prediction to which this system is ultimately linked lie outside the realm of history. But prediction is always the bottom line. It is what gives science its empirical content and its connection with nature. And it is what divides science (no matter how pompous and fictitious) from pure fantasy.
This is not to say that prediction is the purpose of science. It was once, we might say, when science was young and little; for success in prediction was, we saw, the survival value of our innate standards of subjective similarity. But prediction is only one purpose among others now. A more conspicuous purpose is technology, and an overwhelming one is satisfaction of pure intellectual curiosity -- which may once have had its survival value too.
这并不是说预言是科学的目的。我们可以说,预言曾经是襁褓阶段的科学的目的,因为我们天生的主观相似性标准的生存价值,我们看到,就在于预言的成功性。但如今,预言只是科学的众多目的之一。一个更显眼的目的是技术。另一个压倒性的目的是对纯粹的求知欲的满足,而纯粹的求知欲本身可能也曾经是有它的生存价值的。
GOOGLE: This is not to say that prediction is the purpose of science. We might say that prediction was the purpose of science in its infancy, because the survival value of our innate subjective criterion of similarity, as we saw earlier, lies in the success of prediction. But today, prediction is only one of the many purposes of science. A more visible purpose is technology. Another overwhelming purpose is the satisfaction of pure intellectual curiosity, and pure intellectual curiosity may have had its survival value.
[1]这个概念可以表达为一个四位谓词:对u来说,xy比与z更相似。——译者注
[2]选自英国古典学家和诗人阿尔弗雷德·爱德华·豪斯曼(1859——1936)的作品“Fragment of a Greek Tragedy”1883)。——译者注
继续阅读
阅读原文