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科学(science)

已有 974 次阅读 2015-5-2 02:20 |关键词:science

科学[science]
指发现、积累并公认的普遍真理或普遍定理的运用,已系统化和公式化了的知识。科学是对已知世界通过大众可理解的数据计算、文字解释、语言说明、形象展示的一种总结、归纳和认证;科学不是认识世界的唯一渠道,但是具有公允性。

不会互相违背
科学是宇宙宇宙的现象和规律,宇宙所定下的规律不会互相否定,例如宇宙不会规定它的规定是错误,宇宙不会规定既能穿越时空,又规定不能穿越时空,在这两个规定中宇宙只能规定一个是对的,另一个是错误的。穿越时空本身就是一个驳论,认为穿越时空科学就是迷信。
有意义的存在
宇宙定下的规律不会没有意义,例如宇宙不会规定在宇宙什么都不存在,一成不变的存在没有意义,所以宇宙中的物体才会运动,出现生命这种存在。
科学原则
对于科学的核心特征或者说所谓科学精神,随着人类的进步,有不同的观点,一般认为科学具有如下特征:
  • 理性客观:从事科学研究一般不以“神”、“鬼”、“上帝”为前提(一些科学家仍会信仰宗教,但是"科学"本身是理性思维的结果),一切以客观事实的观察为基础,通常科学家会设计实验并控制各种变因来保证实验的准确性,以及解释理论的能力。
  • 可证伪:这是来自卡尔·波普尔的观点,人类其实无法知道一门学问里的理论是否一定正确,但若这门学问有部份有错误时,人们可以严谨明确的证明这部分的错误,的确是错的,那这门学问就算是合乎科学的学问。
  • 存在一个适用范围:也就是说可以不是放之四海皆准的绝对真理。例如:广义相对论在微观世界失效,量子理论在宏观世界失效。不过科学家们仍然努力寻找与探索是否有某种理论可以囊括所有自然现象(至少在物理界,将相对论与量子力学合并是一至少延续数十年的野心)。
  • 普遍必然性:科学理论来自于实践,也必须回到实践,它必须能够解释其适用范围内的已知的所有事实。
科学还可以分为从理论应用等多个层次。
在与社会进步的相互作用中,科学对实践的指导作用得到不断加强,科学体系本身也不断壮大,它对人类历史的重大影响日趋显著。

基本诠释
科学是获取知识的过程,而非知识本身。Science is actually a process used to solve problems or develop an understanding of natural events that involves testing possible answers.
科学方法
这个过程又被称作科学方法,其涵义是通过组织一个经严格验证被认定可信的解决问题的方案来获取信息。The scientific method is a way of gaining information (facts) about the world by forming possible solutions to questions followed by rigorous testing to determine if the proposed solutions are valid.
几个前提
当使用科学方法时,我们假设几个前提:
(1)我们观察的事物都是有特征的,there are specific causes for events observed in the natural world,
(2)这些特征是可以识别的,that the causes can be identified,
(3)自然界当中发生的事件可以通过被普遍接受的方式描述出来,that there are general rules or patterns that can be used to describe what happens in nature,
(4)可以重复的事件可能含有共同的特征,that an event that occurs repeatedly probably has the same cause,
(5)一个人可以感知的,其他人也可以感知,that what one person perceives can be perceived by others, and
(6)基本自然法则不因时间空间改变。That the same fundamental rules of nature apply regardless of where and when they occur.
4、科学方法包含以下重要元素:严谨的观察、构建假说并验证之、对新信息新点子的开放性、自愿接受他人的经过验证的成果。
5、观察。限于我们的感官(嗅觉视觉听觉味觉触觉),或者我们感官的延伸(显微镜录音机X光、温度计等等)。
6、质疑探究。过于复杂和广泛的提问可能无法得到解决,提问的“好坏”直接决定问题是否能够被解决。提出问题后需要做的是探究,即收集关于此命题的信息,参考别人做过的事,可以启发思路,节省时间,或者干脆避免浪费时间。
7、假说,假说是可以被验证的对特定问题的可能的答案。一个好的假说必须是逻辑严密的,能够包含现有的所有信息并对将来可能补充的信息开放。如果有多个选择,一定要选择最简单包含最少假设的那个假说。
8、验证假说。假说可以简单的通过收集其他来源的信息加以验证,也可以通过额外的观察加以验证,更多的时候需要通过设计一个实验来加以验证。实验通过再现一个事件使得科学家可以对假说加以验证。一个事件中往往有多个变量variable,变量越多,实验越难以进行。因此需要可控的实验,经典的可控实验分两组进行,一组称为控制组;另一组称为实验组。科学家们往往不会接受单个实验的结果,因为那有可能只是与实验变量无因果关系的随机事件。只有大量的重复实验皆表现出明显的因果关系,这个实验才可信。
9、理论法则。理论是有关于用来解释事情为什么发生的基本概念的普遍接受的、合理的归纳。科学法则是用来描述自然界中发生了什么的不变的、恒定的自然事实。.从不同的特定的事件中发展出普遍的原则的方法称为归纳;其逆向过程称为推理(deductive/deductive reasoning)
10、交流。科学方法的核心特征之一就是交流。绝大多数情况下,科学研究的结果必须要接受其他对此研究感兴趣的人的监督、审查。交流发生在科学探索的人和一个步骤中,包括发表文章,公开想法和思路。
11、科学的态度。一个科学家必须首先是一个健康的怀疑论者。他必须分得清事实和主张。一件事是否科学取决于它是否被众多严密的证据支持,而非听起来是否响亮。另外,科学家必须十分关注细节,对诚实有强烈的道德认同感。
12、科学与非科学。科学与非科学的根本区别在于假设能否被验证。比如,我们可以假设如果西安事变中蒋介石被杀,抗日战争将会更快的取得胜利。但是这一假设无法得到验证,所以历史不是科学。但是历史、文学、社会学、经济学、哲学也都有其具有逻辑的核心思想。同时,科学与非科学的并不是一成不变的,比如经济学,其中也使用了大量的科学方法来辅助解释经济现象,但总的来说,它与科学还相距甚远。
13、伪科学pseudoscience,伪科学不是科学,却用“科学”的外表和“科学”的语言来说服、迷惑和误导人们认为它是科学可信的。但它们经不起真正的科学的检验。例如,营养学的确是一门科学,但是许多人打营养品的广告正是利用营养学的幌子。我们都知道人体需要诸如氨基酸维生素矿物质等各种营养素,如果营养素缺乏身体就会出现故障。许多科学实验都验证了这一点。而绝大多数情况下,那些保健品的功效远没有它们的广告吹得那样神,我们的身体也并不像它们的广告宣传的那样需要这些保健品。在这些广告中,精心选择的断章取义的科学信息(氨基酸、维生素、矿物质为人体必需)的确使人们感觉这些产品非常可信。事实上,绝大多数人的日常饮食中包含足量足数的营养素,而不需要额外服用保健品。需要特别说明的是,这些保健品往往贴上纯天然的标签,以宣传它们是无毒无副作用并且功效显著的。不过,箭毒素、马钱子碱尼古丁可卡因同样是纯天然的物质,我想没有人愿意在自己的食谱里面添加它们。
14、科学的局限。由科学的定义我们知道,它是寻找信息解决问题的方法,所以科学只能解决有客观现实基础的问题。而诸如道德、价值判断、社会取向、个人态度这些问题是无法用科学方法加以解决的。同时,科学也受到人们从自然现象中探寻本质的能力的限制。人会犯错,同时,由于信息的缺乏或者误解,人们有时候也会得出错误的结论。但是科学本身是具有自我纠错能力的,当我们获取了新的知识,就必须改变或者抛弃原本错误的想法。因此,虽然看起来,地心说是一种错误的结论,但是在当时,它是通过科学方法构建起来的,只是受限于人的观察能力。
15、“若一确信而始者,将止于怀疑;而一怀疑而始者,将止于确信。”

科学方法
任何研究方法要被视为科学方法,则必须是客观(科学家们不能对于科学方法下产生的单一结果有不同的解释或不能去改变结果的发生)。另一项基本期待,则是必须有完整的资料文件以供佐证,以及研究方法必须由第三者小心检视,并且确认该方法能重制。
一般理解,科学是对自然规律的追求。科学定律,有一个重要的标准,就是在某种情况下相对的不能有反例。任何一个客观存在的,能够重复的现象,如果于已有的科学定律矛盾,即宣布此科学定律有一定的局限性。
科学方法使用可再现的方法解释自然现象。从预测当中提出思想实验或假设。预测是在确认实验或观察前提出的,用于证明其中没有受到干预。而对预测的反证则是进步的证明。 科学研究者提出假说来解释自然现象,然后设计实验来检验这些假说,这种实验需要在可控条件下模拟自然现象(在观测科学,如天文学或地质学,可预测的观察结果可以替代核对实验)。整体而言,科学方法可以解决极度创新的问题而又不受主观偏见的影响(又称确认偏误).
经典的科学方法有两大类,即实验方法和理性方法,具体的说主要就是归纳法演绎法
归纳法
将特殊陈述上升为一般陈述(或定律定理原理)的方法。经验科学来源于观察和实验,把大量的原始记录归并为很少的定律定理,形成秩序井然的知识体系,这就是经验科学形成的过程。可见怎样的归纳是有效的、可靠的,这是经验科学要研究的最重要的问题。自从严格意义上的科学延生以来,从未停止过这方面的探索和争论。
演绎法
应用一般陈述(或公理定律定理原理)导出特殊陈述或从一种陈述导出另一种陈述的方法。在演绎论证中,普遍性结论是依据,而个别性结论是论点。演绎推理归纳推理相反,它反映了论据与论点之间由一般到个别的逻辑关系。
演绎推理的主要形式是三段论,即大前提、小前提和结论。大前提是一般事理;小前提是论证的个别事物;结论就是论点。用演绎法进行论证,必须符合演绎推理的形式。
http://baike.baidu.com/link?url=d6yWy9BaF-JBhsnNH3SW3A3NN7JioMUcG8VkGdZ2NspYnhtdtUt4nw3A7181xsqff-3InXlF8eBhohi4-5PEhODuULYGPq6mnj_x141tWv3


Science (from Latin scientia, meaning "knowledge"[2]) is a systematic enterprise that builds and organizes knowledge in the form of testable explanations andpredictions about the universe.[nb 1] In an older and closely related meaning, "science" also refers to this body of knowledge itself, of the type that can be rationally explained and reliably applied. Ever since classical antiquity, science as a type of knowledge has been closely linked to philosophy. In the Westduring the early modern period the words "science" and "philosophy of nature" were sometimes used interchangeably,[3]:p.3 and until the 19th century natural philosophy (which is today called "natural science") was considered a branch of philosophy.[4]
Philosophy of science
Main article: Philosophy of science
The following text needs to be harmonized with text in Philosophy of science.

Working scientists usually take for granted a set of basic assumptions that are needed to justify the scientific method: (1) that there is an objective reality shared by all rational observers; (2) that this objective reality is governed by natural laws; (3) that these laws can be discovered by means of systematic observation and experimentation.[8] Philosophy of science seeks a deep understanding of what these underlying assumptions mean and whether they are valid.

The belief that scientific theories should and do represent metaphysical reality is known as realism. It can be contrasted with anti-realism, the view that the success of science does not depend on it being accurate about unobservable entities such as electrons. One form of anti-realism is idealism, the belief that the mind or consciousness is the most basic essence, and that each mind generates its own reality.[28] In an idealistic world view, what is true for one mind need not be true for other minds.

The Sand Reckoner is a work by Archimedes in which he sets out to determine an upper bound for the number of grains of sand that fit into the universe. In order to do this, he had to estimate the size of the universe according to the contemporary model, and invent a way to analyze extremely large numbers.

There are different schools of thought in philosophy of science. The most popular position is empiricism,[29] which holds that knowledge is created by a process involving observation and that scientific theories are the result of generalizations from such observations.[30] Empiricism generally encompasses inductivism, a position that tries to explain the way general theories can be justified by the finite number of observations humans can make and hence the finite amount of empirical evidence available to confirm scientific theories. This is necessary because the number of predictions those theories make is infinite, which means that they cannot be known from the finite amount of evidence using deductive logic only. Many versions of empiricism exist, with the predominant ones being bayesianism[31] and the hypothetico-deductive method.[32]:p236

Empiricism has stood in contrast to rationalism, the position originally associated with Descartes, which holds that knowledge is created by the human intellect, not by observation.[32]:p20 Critical rationalism is a contrasting 20th-century approach to science, first defined by Austrian-British philosopher Karl Popper. Popper rejected the way that empiricism describes the connection between theory and observation. He claimed that theories are not generated by observation, but that observation is made in the light of theories and that the only way a theory can be affected by observation is when it comes in conflict with it.[32]:pp63–7 Popper proposed replacing verifiability with falsifiability as the landmark of scientific theories, and replacing induction with falsification as the empirical method.[32]:p68 Popper further claimed that there is actually only one universal method, not specific to science: the negative method of criticism, trial and error.[33] It covers all products of the human mind, including science, mathematics, philosophy, and art.[34]

Another approach, instrumentalism, colloquially termed "shut up and calculate", emphasizes the utility of theories as instruments for explaining and predicting phenomena.[35] It views scientific theories as black boxes with only their input (initial conditions) and output (predictions) being relevant. Consequences, theoretical entities and logical structure are claimed to be something that should simply be ignored and that scientists shouldn't make a fuss about (see interpretations of quantum mechanics). Close to instrumentalism isconstructive empiricism, according to which the main criterion for the success of a scientific theory is whether what it says about observable entities is true.

Paul K Feyerabend advanced the idea of epistemological anarchism, which holds that there are no useful and exception-free methodological rules governing the progress of science or the growth of knowledge, and that the idea that science can or should operate according to universal and fixed rules is unrealistic, pernicious and detrimental to science itself.[36] Feyerabend advocates treating science as an ideologyalongside others such as religionmagic and mythology, and considers the dominance of science in society authoritarian and unjustified. He also contended (along with Imre Lakatos)[discuss] that the demarcation problem of distinguishing science from pseudoscience on objective grounds is not possible and thus fatal to the notion of science running according to fixed, universal rules.[36] Feyerabend also stated that science does not have evidence for its philosophical precepts, particularly the notion of Uniformity of Law and the Uniformity of Process across time and space.[37]

Finally, another approach often cited in debates of scientific skepticism against controversial movements like "scientific creationism", is methodological naturalism. Its main point is that a difference between natural andsupernatural explanations should be made, and that science should be restricted methodologically to natural explanations.[38] That the restriction is merely methodological (rather than ontological) means that science should not consider supernatural explanations itself, but should not claim them to be wrong either. Instead, supernatural explanations should be left a matter of personal belief outside the scope of science. Methodological naturalism maintains that proper science requires strict adherence to empirical study and independent verification as a process for properly developing and evaluating explanations for observable phenomena.[39] The absence of these standards, arguments from authority, biased observational studies and other common fallacies are frequently cited by supporters of methodological naturalism as characteristic of the non-science they criticize.

Certainty and science
The DNA double helix is amolecule that encodes thegenetic instructions used in the development and functioning of all known living organisms and manyviruses.

A scientific theory is empirical,[29][40] and is always open to falsification if new evidence is presented. That is, no theory is ever considered strictly certain as science accepts the concept offallibilism.[41] The philosopher of science Karl Popper sharply distinguishes truth from certainty. He writes that scientific knowledge "consists in the search for truth", but it "is not the search for certainty ... All human knowledge is fallible and therefore uncertain."[42]:p4

New scientific knowledge rarely results in vast changes in our understanding. According to psychologist Keith Stanovich, it may be the media's overuse of words like "breakthrough" that leads the public to imagine that science is constantly proving everything it thought was true to be false.[43]:119–138 While there are such famous cases as the theory of relativity that required a complete reconceptualization, these are extreme exceptions. Knowledge in science is gained by a gradual synthesis of information from different experiments, by various researchers, across different branches of science; it is more like a climb than a leap.[43]:123 Theories vary in the extent to which they have been tested and verified, as well as their acceptance in the scientific community.[44] For example,heliocentric theorythe theory of evolutionrelativity theory, and germ theory still bear the name "theory" even though, in practice, they are considered factual.[45] Philosopher Barry Stroud adds that, although the best definition for "knowledge" is contested, being skeptical and entertaining the possibility that one is incorrect is compatible with being correct. Ironically then, the scientist adhering to proper scientific approaches will doubt themselves even once they possess the truth.[46] The fallibilist C. S. Peirce argued that inquiry is the struggle to resolve actual doubt and that merely quarrelsome, verbal, or hyperbolic doubt is fruitless[47]—but also that the inquirer should try to attain genuine doubt rather than resting uncritically on common sense.[48] He held that the successful sciences trust, not to any single chain of inference (no stronger than its weakest link), but to the cable of multiple and various arguments intimately connected.[49]

Stanovich also asserts that science avoids searching for a "magic bullet"; it avoids the single-cause fallacy. This means a scientist would not ask merely "What is the cause of ...", but rather "What arethe most significant causes of ...". This is especially the case in the more macroscopic fields of science (e.g. psychologycosmology).[43]:141–147 Of course, research often analyzes few factors at once, but these are always added to the long list of factors that are most important to consider.[43]:141–147 For example: knowing the details of only a person's genetics, or their history and upbringing, or the current situation may not explain a behaviour, but a deep understanding of all these variables combined can be very predictive.

Fringe science, pseudoscience and junk science

An area of study or speculation that masquerades as science in an attempt to claim a legitimacy that it would not otherwise be able to achieve is sometimes referred to as pseudosciencefringe science, or junk science.[50] Physicist Richard Feynman coined the term "cargo cult science" for cases in which researchers believe they are doing science because their activities have the outward appearance of science but actually lack the "kind of utter honesty" that allows their results to be rigorously evaluated.[51] Various types of commercial advertising, ranging from hype to fraud, may fall into these categories.

There also can be[discuss] an element of political or ideological bias on all sides of scientific debates.[citation needed] Sometimes, research may be characterized as "bad science", research that may be well-intentioned but is actually incorrect, obsolete, incomplete, or over-simplified expositions of scientific ideas. The term "scientific misconduct" refers to situations such as where researchers have intentionally misrepresented their published data or have purposely given credit for a discovery to the wrong person.[52]

Scientific practice
Astronomy became much more accurate after Tycho Brahe devised hisscientific instruments for measuring angles between two celestial bodies, before the invention of the telescope. Brahe's observations were the basis for Kepler's laws.

Although encyclopedias such as Pliny (fl. 77 AD) Natural History offered purported fact, they proved unreliable. A skeptical point of view, demanding a method of proof, was the practical position taken to deal with unreliable knowledge. As early as 1000 years ago, scholars such as Alhazen (Doubts Concerning Ptolemy), Roger BaconWiteloJohn Pecham, Francis Bacon (1605), and C. S. Peirce (1839–1914) provided the community to address these points of uncertainty. In particular, fallacious reasoning can be exposed, such as 'affirming the consequent'.

"If a man will begin with certainties, he shall end in doubts; but if he will be content to begin with doubts, he shall end in certainties." —Francis Bacon (1605) The Advancement of Learning, Book 1, v, 8

The methods of inquiry into a problem have been known for thousands of years,[53] and extend beyond theory to practice. The use of measurements, for example, is a practical approach to settle disputes in the community.

John Ziman points out that intersubjective pattern recognition is fundamental to the creation of all scientific knowledge.[54]:p44 Ziman shows how scientists can identify patterns to each other across centuries: Ziman refers to this ability as 'perceptual consensibility'.[55]:p46 Ziman then makes consensibility, leading to consensus, the touchstone of reliable knowledge.[55]:p104

The scientific method
Main article: Scientific method

The scientific method seeks to explain the events of nature in a reproducible way.[56] An explanatory thought experiment or hypothesis is put forward, as explanation, using principles such as parsimony (also known as "Occam's Razor") and are generally expected to seek consilience—fitting well with other accepted facts related to the phenomena.[57] This new explanation is used to make falsifiablepredictions that are testable by experiment or observation. The predictions are to be posted before a confirming experiment or observation is sought, as proof that no tampering has occurred. Disproof of a prediction is evidence of progress.[58][59] This is done partly through observation of natural phenomena, but also through experimentation, that tries to simulate natural events under controlled conditions, as appropriate to the discipline (in the observational sciences, such as astronomy or geology, a predicted observation might take the place of a controlled experiment). Experimentation is especially important in science to help establish causal relationships (to avoid the correlation fallacy).

Isaac Newton, shown here in a 1689 portrait, made seminal contributions to classical mechanicsgravity, and optics. Newton shares credit with Gottfried Leibniz for the development of calculus.

When a hypothesis proves unsatisfactory, it is either modified or discarded.[60] If the hypothesis survived testing, it may become adopted into the framework of ascientific theory. This is a logically reasoned, self-consistent model or framework for describing the behavior of certain natural phenomena. A theory typically describes the behavior of much broader sets of phenomena than a hypothesis; commonly, a large number of hypotheses can be logically bound together by a single theory. Thus a theory is a hypothesis explaining various other hypotheses. In that vein, theories are formulated according to most of the same scientific principles as hypotheses. In addition to testing hypotheses, scientists may also generate a model based on observed phenomena. This is an attempt to describe or depict the phenomenon in terms of a logical, physical or mathematical representation and to generate new hypotheses that can be tested.[61]

While performing experiments to test hypotheses, scientists may have a preference for one outcome over another, and so it is important to ensure that science as a whole can eliminate this bias.[62][63] This can be achieved by careful experimental design, transparency, and a thorough peer review process of the experimental results as well as any conclusions.[64][65] After the results of an experiment are announced or published, it is normal practice for independent researchers to double-check how the research was performed, and to follow up by performing similar experiments to determine how dependable the results might be.[66] Taken in its entirety, the scientific method allows for highly creative problem solving while minimizing any effects of subjective bias on the part of its users (namely the confirmation bias).[67]

Mathematics and formal sciences
Main article: Mathematics

Mathematics is essential to the sciences. One important function of mathematics in science is the role it plays in the expression of scientific models. Observing and collecting measurements, as well as hypothesizing and predicting, often require extensive use of mathematics. Arithmeticalgebrageometrytrigonometry and calculus, for example, are all essential to physics. Virtually every branch of mathematics has applications in science, including "pure" areas such as number theory and topology.

Statistical methods, which are mathematical techniques for summarizing and analyzing data, allow scientists to assess the level of reliability and the range of variation in experimental results. Statistical analysis plays a fundamental role in many areas of both the natural sciences and social sciences.

Computational science applies computing power to simulate real-world situations, enabling a better understanding of scientific problems than formal mathematics alone can achieve. According to theSociety for Industrial and Applied Mathematics, computation is now as important as theory and experiment in advancing scientific knowledge.[68]

Whether mathematics itself is properly classified as science has been a matter of some debate. Some thinkers see mathematicians as scientists, regarding physical experiments as inessential or mathematical proofs as equivalent to experiments. Others do not see mathematics as a science, since it does not require an experimental test of its theories and hypotheses. Mathematical theorems and formulas are obtained by logical derivations which presume axiomaticsystems, rather than the combination of empirical observation and logical reasoning that has come to be known as the scientific method. In general, mathematics is classified as formal science, while natural and social sciences are classified as empirical sciences.[69]

Basic and applied research
Anthropogenic pollution has an effect on the Earth's environment and climate.

Although some scientific research is applied research into specific problems, a great deal of our understanding comes from the curiosity-driven undertaking of basic research. This leads to options for technological advance that were not planned or sometimes even imaginable. This point was made by Michael Faraday when, allegedly in response to the question "what is the use of basic research?" he responded "Sir, what is the use of a new-born child?".[70] For example, research into the effects of red light on the human eye's rod cells did not seem to have any practical purpose; eventually, the discovery that our night vision is not troubled by red light would lead search and rescue teams (among others) to adopt red light in the cockpits of jets and helicopters.[43]:106–110 In a nutshell: Basic research is the search for knowledge. Applied research is the search for solutions to practical problems using this knowledge. Finally, even basic research can take unexpected turns, and there is some sense in which the scientific method is built to harness luck.

Research in practice

Due to the increasing complexity of information and specialization of scientists, most of the cutting-edge research today is done by well funded groups of scientists, rather than individuals.[71]D.K. Simonton notes that due to the breadth of very precise and far reaching tools already used by researchers today and the amount of research generated so far, creation of new disciplines or revolutions within a discipline may no longer be possible as it is unlikely that some phenomenon that merits its own discipline has been overlooked. Hybridizing of disciplines and finessing knowledge is, in his view, the future of science.[71]


http://en.wikipedia.org/wiki/Science







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