Scientific method

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"Scientific research" redirects here. Scientific method_sentence_0

For the publisher, see Scientific Research Publishing. Scientific method_sentence_1

For other uses, see Scientific method (disambiguation). Scientific method_sentence_2

For broader coverage of this topic, see Research. Scientific method_sentence_3

The scientific method is an empirical method of acquiring knowledge that has characterized the development of science since at least the 17th century. Scientific method_sentence_4

It involves careful observation, applying rigorous skepticism about what is observed, given that cognitive assumptions can distort how one interprets the observation. Scientific method_sentence_5

It involves formulating hypotheses, via induction, based on such observations; experimental and measurement-based testing of deductions drawn from the hypotheses; and refinement (or elimination) of the hypotheses based on the experimental findings. Scientific method_sentence_6

These are principles of the scientific method, as distinguished from a definitive series of steps applicable to all scientific enterprises. Scientific method_sentence_7

Though diverse models for the scientific method are available, there is in general a continuous process that includes observations about the natural world. Scientific method_sentence_8

People are naturally inquisitive, so they often come up with questions about things they see or hear, and they often develop ideas or hypotheses about why things are the way they are. Scientific method_sentence_9

The best hypotheses lead to predictions that can be tested in various ways. Scientific method_sentence_10

The most conclusive testing of hypotheses comes from reasoning based on carefully controlled experimental data. Scientific method_sentence_11

Depending on how well additional tests match the predictions, the original hypothesis may require refinement, alteration, expansion or even rejection. Scientific method_sentence_12

If a particular hypothesis becomes very well supported, a general theory may be developed. Scientific method_sentence_13

Although procedures vary from one field of inquiry to another, they are frequently the same from one to another. Scientific method_sentence_14

The process of the scientific method involves making conjectures (hypotheses), deriving predictions from them as logical consequences, and then carrying out experiments or empirical observations based on those predictions. Scientific method_sentence_15

A hypothesis is a conjecture, based on knowledge obtained while seeking answers to the question. Scientific method_sentence_16

The hypothesis might be very specific, or it might be broad. Scientific method_sentence_17

Scientists then test hypotheses by conducting experiments or studies. Scientific method_sentence_18

A scientific hypothesis must be falsifiable, implying that it is possible to identify a possible outcome of an experiment or observation that conflicts with predictions deduced from the hypothesis; otherwise, the hypothesis cannot be meaningfully tested. Scientific method_sentence_19

The purpose of an experiment is to determine whether observations agree with or conflict with the predictions derived from a hypothesis. Scientific method_sentence_20

Experiments can take place anywhere from a garage to CERN's Large Hadron Collider. Scientific method_sentence_21

There are difficulties in a formulaic statement of method, however. Scientific method_sentence_22

Though the scientific method is often presented as a fixed sequence of steps, it represents rather a set of general principles. Scientific method_sentence_23

Not all steps take place in every scientific inquiry (nor to the same degree), and they are not always in the same order. Scientific method_sentence_24

History Scientific method_section_0

Main article: History of scientific method Scientific method_sentence_25

See also: Timeline of the history of scientific method Scientific method_sentence_26

Important debates in the history of science concern rationalism, especially as advocated by René Descartes; inductivism and/or empiricism, as argued for by Francis Bacon, and rising to particular prominence with Isaac Newton and his followers; and hypothetico-deductivism, which came to the fore in the early 19th century. Scientific method_sentence_27

The term "scientific method" emerged in the 19th century, when a significant institutional development of science was taking place and terminologies establishing clear boundaries between science and non-science, such as "scientist" and "pseudoscience", appeared. Scientific method_sentence_28

Throughout the 1830s and 1850s, by which time Baconianism was popular, naturalists like William Whewell, John Herschel, John Stuart Mill engaged in debates over "induction" and "facts" and were focused on how to generate knowledge. Scientific method_sentence_29

In the late 19th and early 20th centuries, a debate over realism vs. antirealism was conducted as powerful scientific theories extended beyond the realm of the observable. Scientific method_sentence_30

The term "scientific method" came into popular use in the twentieth century, popping up in dictionaries and science textbooks, although there was little scientific consensus over its meaning. Scientific method_sentence_31

Although there was a growth through the middle of the twentieth century, by the 1960s and 1970s numerous influential philosophers of science such as Thomas Kuhn and Paul Feyerabend had questioned the universality of the "scientific method" and in doing so largely replaced the notion of science as a homogeneous and universal method with that of it being a heterogeneous and local practice. Scientific method_sentence_32

In particular, Paul Feyerabend, in the 1975 first edition of his book Against Method, argued against there being any universal rules of science. Scientific method_sentence_33

Later examples include physicist Lee Smolin's 2013 essay "There Is No Scientific Method" and historian of science Daniel Thurs's chapter in the 2015 book Newton's Apple and Other Myths about Science, which concluded that the scientific method is a myth or, at best, an idealization. Scientific method_sentence_34

Philosophers Robert Nola and Howard Sankey, in their 2007 book Theories of Scientific Method, said that debates over scientific method continue, and argued that Feyerabend, despite the title of Against Method, accepted certain rules of method and attempted to justify those rules with a metamethodology. Scientific method_sentence_35

Overview Scientific method_section_1

The DNA example below is a synopsis of this method. Scientific method_sentence_36

The scientific method is the process by which science is carried out. Scientific method_sentence_37

As in other areas of inquiry, science (through the scientific method) can build on previous knowledge and develop a more sophisticated understanding of its topics of study over time. Scientific method_sentence_38

This model can be seen to underlie the scientific revolution. Scientific method_sentence_39

The ubiquitous element in scientific method is empiricism. Scientific method_sentence_40

This is in opposition to stringent forms of rationalism: the scientific method embodies that reason alone cannot solve a particular scientific problem. Scientific method_sentence_41

A strong formulation of the scientific method is not always aligned with a form of empiricism in which the empirical data is put forward in the form of experience or other abstracted forms of knowledge; in current scientific practice, however, the use of scientific modelling and reliance on abstract typologies and theories is normally accepted. Scientific method_sentence_42

The scientific method is of necessity also an expression of an opposition to claims that e.g. revelation, political or religious dogma, appeals to tradition, commonly held beliefs, common sense, or, importantly, currently held theories, are the only possible means of demonstrating truth. Scientific method_sentence_43

Different early expressions of empiricism and the scientific method can be found throughout history, for instance with the ancient Stoics, Epicurus, Alhazen, Roger Bacon, and William of Ockham. Scientific method_sentence_44

From the 16th century onwards, experiments were advocated by Francis Bacon, and performed by Giambattista della Porta, Johannes Kepler, and Galileo Galilei. Scientific method_sentence_45

There was particular development aided by theoretical works by Francisco Sanches, John Locke, George Berkeley, and David Hume. Scientific method_sentence_46

The hypothetico-deductive model formulated in the 20th century, is the ideal although it has undergone significant revision since first proposed (for a more formal discussion, see below). Scientific method_sentence_47

Staddon (2017) argues it is a mistake to try following rules which are best learned through careful study of examples of scientific investigation. Scientific method_sentence_48

Process Scientific method_section_2

The overall process involves making conjectures (hypotheses), deriving predictions from them as logical consequences, and then carrying out experiments based on those predictions to determine whether the original conjecture was correct. Scientific method_sentence_49

There are difficulties in a formulaic statement of method, however. Scientific method_sentence_50

Though the scientific method is often presented as a fixed sequence of steps, these actions are better considered as general principles. Scientific method_sentence_51

Not all steps take place in every scientific inquiry (nor to the same degree), and they are not always done in the same order. Scientific method_sentence_52

As noted by scientist and philosopher William Whewell (1794–1866), "invention, sagacity, [and] genius" are required at every step. Scientific method_sentence_53

Formulation of a question Scientific method_section_3

The question can refer to the explanation of a specific observation, as in "Why is the sky blue?" Scientific method_sentence_54

but can also be open-ended, as in "How can I design a drug to cure this particular disease?" Scientific method_sentence_55

This stage frequently involves finding and evaluating evidence from previous experiments, personal scientific observations or assertions, as well as the work of other scientists. Scientific method_sentence_56

If the answer is already known, a different question that builds on the evidence can be posed. Scientific method_sentence_57

When applying the scientific method to research, determining a good question can be very difficult and it will affect the outcome of the investigation. Scientific method_sentence_58

Hypothesis Scientific method_section_4

A hypothesis is a conjecture, based on knowledge obtained while formulating the question, that may explain any given behavior. Scientific method_sentence_59

The hypothesis might be very specific; for example, Einstein's equivalence principle or Francis Crick's "DNA makes RNA makes protein", or it might be broad; for example, unknown species of life dwell in the unexplored depths of the oceans. Scientific method_sentence_60

A statistical hypothesis is a conjecture about a given statistical population. Scientific method_sentence_61

For example, the population might be people with a particular disease. Scientific method_sentence_62

The conjecture might be that a new drug will cure the disease in some of those people. Scientific method_sentence_63

Terms commonly associated with statistical hypotheses are null hypothesis and alternative hypothesis. Scientific method_sentence_64

A null hypothesis is the conjecture that the statistical hypothesis is false; for example, that the new drug does nothing and that any cure is caused by chance. Scientific method_sentence_65

Researchers normally want to show that the null hypothesis is false. Scientific method_sentence_66

The alternative hypothesis is the desired outcome, that the drug does better than chance. Scientific method_sentence_67

A final point: a scientific hypothesis must be falsifiable, meaning that one can identify a possible outcome of an experiment that conflicts with predictions deduced from the hypothesis; otherwise, it cannot be meaningfully tested. Scientific method_sentence_68

Prediction Scientific method_section_5

This step involves determining the logical consequences of the hypothesis. Scientific method_sentence_69

One or more predictions are then selected for further testing. Scientific method_sentence_70

The more unlikely that a prediction would be correct simply by coincidence, then the more convincing it would be if the prediction were fulfilled; evidence is also stronger if the answer to the prediction is not already known, due to the effects of hindsight bias (see also postdiction). Scientific method_sentence_71

Ideally, the prediction must also distinguish the hypothesis from likely alternatives; if two hypotheses make the same prediction, observing the prediction to be correct is not evidence for either one over the other. Scientific method_sentence_72

(These statements about the relative strength of evidence can be mathematically derived using Bayes' Theorem). Scientific method_sentence_73

Testing Scientific method_section_6

This is an investigation of whether the real world behaves as predicted by the hypothesis. Scientific method_sentence_74

Scientists (and other people) test hypotheses by conducting experiments. Scientific method_sentence_75

The purpose of an experiment is to determine whether observations of the real world agree with or conflict with the predictions derived from a hypothesis. Scientific method_sentence_76

If they agree, confidence in the hypothesis increases; otherwise, it decreases. Scientific method_sentence_77

Agreement does not assure that the hypothesis is true; future experiments may reveal problems. Scientific method_sentence_78

Karl Popper advised scientists to try to falsify hypotheses, i.e., to search for and test those experiments that seem most doubtful. Scientific method_sentence_79

Large numbers of successful confirmations are not convincing if they arise from experiments that avoid risk. Scientific method_sentence_80

Experiments should be designed to minimize possible errors, especially through the use of appropriate scientific controls. Scientific method_sentence_81

For example, tests of medical treatments are commonly run as double-blind tests. Scientific method_sentence_82

Test personnel, who might unwittingly reveal to test subjects which samples are the desired test drugs and which are placebos, are kept ignorant of which are which. Scientific method_sentence_83

Such hints can bias the responses of the test subjects. Scientific method_sentence_84

Furthermore, failure of an experiment does not necessarily mean the hypothesis is false. Scientific method_sentence_85

Experiments always depend on several hypotheses, e.g., that the test equipment is working properly, and a failure may be a failure of one of the auxiliary hypotheses. Scientific method_sentence_86

(See the Duhem–Quine thesis.) Scientific method_sentence_87

Experiments can be conducted in a college lab, on a kitchen table, at CERN's Large Hadron Collider, at the bottom of an ocean, on Mars (using one of the working rovers), and so on. Scientific method_sentence_88

Astronomers do experiments, searching for planets around distant stars. Scientific method_sentence_89

Finally, most individual experiments address highly specific topics for reasons of practicality. Scientific method_sentence_90

As a result, evidence about broader topics is usually accumulated gradually. Scientific method_sentence_91

Analysis Scientific method_section_7

This involves determining what the results of the experiment show and deciding on the next actions to take. Scientific method_sentence_92

The predictions of the hypothesis are compared to those of the null hypothesis, to determine which is better able to explain the data. Scientific method_sentence_93

In cases where an experiment is repeated many times, a statistical analysis such as a chi-squared test may be required. Scientific method_sentence_94

If the evidence has falsified the hypothesis, a new hypothesis is required; if the experiment supports the hypothesis but the evidence is not strong enough for high confidence, other predictions from the hypothesis must be tested. Scientific method_sentence_95

Once a hypothesis is strongly supported by evidence, a new question can be asked to provide further insight on the same topic. Scientific method_sentence_96

Evidence from other scientists and experience are frequently incorporated at any stage in the process. Scientific method_sentence_97

Depending on the complexity of the experiment, many iterations may be required to gather sufficient evidence to answer a question with confidence or to build up many answers to highly specific questions in order to answer a single broader question. Scientific method_sentence_98

DNA example Scientific method_section_8

The basic elements of the scientific method are illustrated by the following example from the discovery of the structure of DNA: Scientific method_sentence_99

Scientific method_unordered_list_0

  • Question: Previous investigation of DNA had determined its chemical composition (the four nucleotides), the structure of each individual nucleotide, and other properties. X-ray diffraction patterns of DNA by Florence Bell in her Ph.D. thesis (1939) were similar to (although not as good as) "photo 51", but this research was interrupted by the events of World War II. DNA had been identified as the carrier of genetic information by the Avery–MacLeod–McCarty experiment in 1944, but the mechanism of how genetic information was stored in DNA was unclear.Scientific method_item_0_0
  • Hypothesis: Linus Pauling, Francis Crick and James D. Watson hypothesized that DNA had a helical structure.Scientific method_item_0_1
  • Prediction: If DNA had a helical structure, its X-ray diffraction pattern would be X-shaped. This prediction was determined using the mathematics of the helix transform, which had been derived by Cochran, Crick and Vand (and independently by Stokes). This prediction was a mathematical construct, completely independent from the biological problem at hand.Scientific method_item_0_2
  • Experiment: Rosalind Franklin used pure DNA to perform X-ray diffraction to produce photo 51. The results showed an X-shape.Scientific method_item_0_3
  • Analysis: When Watson saw the detailed diffraction pattern, he immediately recognized it as a helix. He and Crick then produced their model, using this information along with the previously known information about DNA's composition, especially Chargaff's rules of base pairing.Scientific method_item_0_4

The discovery became the starting point for many further studies involving the genetic material, such as the field of molecular genetics, and it was awarded the Nobel Prize in 1962. Scientific method_sentence_100

Each step of the example is examined in more detail later in the article. Scientific method_sentence_101

Other components Scientific method_section_9

The scientific method also includes other components required even when all the iterations of the steps above have been completed: Scientific method_sentence_102

Replication Scientific method_section_10

If an experiment cannot be repeated to produce the same results, this implies that the original results might have been in error. Scientific method_sentence_103

As a result, it is common for a single experiment to be performed multiple times, especially when there are uncontrolled variables or other indications of experimental error. Scientific method_sentence_104

For significant or surprising results, other scientists may also attempt to replicate the results for themselves, especially if those results would be important to their own work. Scientific method_sentence_105

Replication has become a contentious issue in social and biomedical science where treatments are administered to groups of individuals. Scientific method_sentence_106

Typically an experimental group gets the treatment, such as drug, and the control group gets a placebo. Scientific method_sentence_107

John Ioannidis in 2005 pointed out that the method being used has led to many findings that cannot be replicated. Scientific method_sentence_108

External review Scientific method_section_11

The process of peer review involves evaluation of the experiment by experts, who typically give their opinions anonymously. Scientific method_sentence_109

Some journals request that the experimenter provide lists of possible peer reviewers, especially if the field is highly specialized. Scientific method_sentence_110

Peer-review does not certify the correctness of the results, only that, in the opinion of the reviewer, the experiments themselves were sound (based on the description supplied by the experimenter). Scientific method_sentence_111

If the work passes peer review, which occasionally may require new experiments requested by the reviewers, it will be published in a peer-reviewed scientific journal. Scientific method_sentence_112

The specific journal that publishes the results indicates the perceived quality of the work. Scientific method_sentence_113

Data recording and sharing Scientific method_section_12

Scientists typically are careful in recording their data, a requirement promoted by Ludwik Fleck (1896–1961) and others. Scientific method_sentence_114

Though not typically required, they might be requested to supply this data to other scientists who wish to replicate their original results (or parts of their original results), extending to the sharing of any experimental samples that may be difficult to obtain. Scientific method_sentence_115

Scientific inquiry Scientific method_section_13

Scientific inquiry generally aims to obtain knowledge in the form of testable explanations that scientists can use to predict the results of future experiments. Scientific method_sentence_116

This allows scientists to gain a better understanding of the topic under study, and later to use that understanding to intervene in its causal mechanisms (such as to cure disease). Scientific method_sentence_117

The better an explanation is at making predictions, the more useful it frequently can be, and the more likely it will continue to explain a body of evidence better than its alternatives. Scientific method_sentence_118

The most successful explanations – those which explain and make accurate predictions in a wide range of circumstances – are often called scientific theories. Scientific method_sentence_119

Most experimental results do not produce large changes in human understanding; improvements in theoretical scientific understanding typically result from a gradual process of development over time, sometimes across different domains of science. Scientific method_sentence_120

Scientific models vary in the extent to which they have been experimentally tested and for how long, and in their acceptance in the scientific community. Scientific method_sentence_121

In general, explanations become accepted over time as evidence accumulates on a given topic, and the explanation in question proves more powerful than its alternatives at explaining the evidence. Scientific method_sentence_122

Often subsequent researchers re-formulate the explanations over time, or combined explanations to produce new explanations. Scientific method_sentence_123

Tow sees the scientific method in terms of an evolutionary algorithm applied to science and technology. Scientific method_sentence_124

Properties of scientific inquiry Scientific method_section_14

Scientific knowledge is closely tied to empirical findings and can remain subject to falsification if new experimental observations are incompatible with what is found. Scientific method_sentence_125

That is, no theory can ever be considered final since new problematic evidence might be discovered. Scientific method_sentence_126

If such evidence is found, a new theory may be proposed, or (more commonly) it is found that modifications to the previous theory are sufficient to explain the new evidence. Scientific method_sentence_127

The strength of a theory can be argued to relate to how long it has persisted without major alteration to its core principles. Scientific method_sentence_128

Theories can also become subsumed by other theories. Scientific method_sentence_129

For example, Newton's laws explained thousands of years of scientific observations of the planets almost perfectly. Scientific method_sentence_130

However, these laws were then determined to be special cases of a more general theory (relativity), which explained both the (previously unexplained) exceptions to Newton's laws and predicted and explained other observations such as the deflection of light by gravity. Scientific method_sentence_131

Thus, in certain cases independent, unconnected, scientific observations can be connected to each other, unified by principles of increasing explanatory power. Scientific method_sentence_132

Since new theories might be more comprehensive than what preceded them, and thus be able to explain more than previous ones, successor theories might be able to meet a higher standard by explaining a larger body of observations than their predecessors. Scientific method_sentence_133

For example, the theory of evolution explains the diversity of life on Earth, how species adapt to their environments, and many other patterns observed in the natural world; its most recent major modification was unification with genetics to form the modern evolutionary synthesis. Scientific method_sentence_134

In subsequent modifications, it has also subsumed aspects of many other fields such as biochemistry and molecular biology. Scientific method_sentence_135

Beliefs and biases Scientific method_section_15

Scientific methodology often directs that hypotheses be tested in controlled conditions wherever possible. Scientific method_sentence_136

This is frequently possible in certain areas, such as in the biological sciences, and more difficult in other areas, such as in astronomy. Scientific method_sentence_137

The practice of experimental control and reproducibility can have the effect of diminishing the potentially harmful effects of circumstance, and to a degree, personal bias. Scientific method_sentence_138

For example, pre-existing beliefs can alter the interpretation of results, as in confirmation bias; this is a heuristic that leads a person with a particular belief to see things as reinforcing their belief, even if another observer might disagree (in other words, people tend to observe what they expect to observe). Scientific method_sentence_139

A historical example is the belief that the legs of a galloping horse are splayed at the point when none of the horse's legs touch the ground, to the point of this image being included in paintings by its supporters. Scientific method_sentence_140

However, the first stop-action pictures of a horse's gallop by Eadweard Muybridge showed this to be false, and that the legs are instead gathered together. Scientific method_sentence_141

Another important human bias that plays a role is a preference for new, surprising statements (see appeal to novelty), which can result in a search for evidence that the new is true. Scientific method_sentence_142

Poorly attested beliefs can be believed and acted upon via a less rigorous heuristic. Scientific method_sentence_143

Goldhaber and Nieto published in 2010 the observation that if theoretical structures with "many closely neighboring subjects are described by connecting theoretical concepts, then the theoretical structure acquires a robustness which makes it increasingly hard – though certainly never impossible – to overturn". Scientific method_sentence_144

When a narrative is constructed its elements become easier to believe. Scientific method_sentence_145

For more on the narrative fallacy, see also , p. 27: "Words and ideas are originally phonetic and mental equivalences of the experiences coinciding with them. Scientific method_sentence_146

... Scientific method_sentence_147

Such proto-ideas are at first always too broad and insufficiently specialized. Scientific method_sentence_148

... Once a structurally complete and closed system of opinions consisting of many details and relations has been formed, it offers enduring resistance to anything that contradicts it." Scientific method_sentence_149

Sometimes, these have their elements assumed a priori, or contain some other logical or methodological flaw in the process that ultimately produced them. Scientific method_sentence_150

Donald M. MacKay has analyzed these elements in terms of limits to the accuracy of measurement and has related them to instrumental elements in a category of measurement. Scientific method_sentence_151

Elements of the scientific method Scientific method_section_16

There are different ways of outlining the basic method used for scientific inquiry. Scientific method_sentence_152

The scientific community and philosophers of science generally agree on the following classification of method components. Scientific method_sentence_153

These methodological elements and organization of procedures tend to be more characteristic of natural sciences than social sciences. Scientific method_sentence_154

Nonetheless, the cycle of formulating hypotheses, testing and analyzing the results, and formulating new hypotheses, will resemble the cycle described below. Scientific method_sentence_155

The scientific method is an iterative, cyclical process through which information is continually revised. Scientific method_sentence_156

It is generally recognized to develop advances in knowledge through the following elements, in varying combinations or contributions: Scientific method_sentence_157

Scientific method_unordered_list_1

  • Characterizations (observations, definitions, and measurements of the subject of inquiry)Scientific method_item_1_5
  • Hypotheses (theoretical, hypothetical explanations of observations and measurements of the subject)Scientific method_item_1_6
  • Predictions (inductive and deductive reasoning from the hypothesis or theory)Scientific method_item_1_7
  • Experiments (tests of all of the above)Scientific method_item_1_8

Each element of the scientific method is subject to peer review for possible mistakes. Scientific method_sentence_158

These activities do not describe all that scientists do (see below) but apply mostly to experimental sciences (e.g., physics, chemistry, and biology). Scientific method_sentence_159

The elements above are often taught in the educational system as "the scientific method". Scientific method_sentence_160

The scientific method is not a single recipe: it requires intelligence, imagination, and creativity. Scientific method_sentence_161

In this sense, it is not a mindless set of standards and procedures to follow, but is rather an ongoing cycle, constantly developing more useful, accurate and comprehensive models and methods. Scientific method_sentence_162

For example, when Einstein developed the Special and General Theories of Relativity, he did not in any way refute or discount Newton's Principia. Scientific method_sentence_163

On the contrary, if the astronomically massive, the feather-light, and the extremely fast are removed from Einstein's theories – all phenomena Newton could not have observed – Newton's equations are what remain. Scientific method_sentence_164

Einstein's theories are expansions and refinements of Newton's theories and, thus, increase confidence in Newton's work. Scientific method_sentence_165

A linearized, pragmatic scheme of the four points above is sometimes offered as a guideline for proceeding: Scientific method_sentence_166

Scientific method_ordered_list_2

  1. Define a questionScientific method_item_2_9
  2. Gather information and resources (observe)Scientific method_item_2_10
  3. Form an explanatory hypothesisScientific method_item_2_11
  4. Test the hypothesis by performing an experiment and collecting data in a reproducible mannerScientific method_item_2_12
  5. Analyze the dataScientific method_item_2_13
  6. Interpret the data and draw conclusions that serve as a starting point for new hypothesisScientific method_item_2_14
  7. Publish resultsScientific method_item_2_15
  8. Retest (frequently done by other scientists)Scientific method_item_2_16

The iterative cycle inherent in this step-by-step method goes from point 3 to 6 back to 3 again. Scientific method_sentence_167

While this schema outlines a typical hypothesis/testing method, a number of philosophers, historians, and sociologists of science, including Paul Feyerabend, claim that such descriptions of scientific method have little relation to the ways that science is actually practiced. Scientific method_sentence_168

Characterizations Scientific method_section_17

The scientific method depends upon increasingly sophisticated characterizations of the subjects of investigation. Scientific method_sentence_169

(The subjects can also be called unsolved problems or the unknowns.) Scientific method_sentence_170

For example, Benjamin Franklin conjectured, correctly, that St. Scientific method_sentence_171 Elmo's fire was electrical in nature, but it has taken a long series of experiments and theoretical changes to establish this. Scientific method_sentence_172

While seeking the pertinent properties of the subjects, careful thought may also entail some definitions and observations; the observations often demand careful measurements and/or counting. Scientific method_sentence_173

The systematic, careful collection of measurements or counts of relevant quantities is often the critical difference between pseudo-sciences, such as alchemy, and science, such as chemistry or biology. Scientific method_sentence_174

Scientific measurements are usually tabulated, graphed, or mapped, and statistical manipulations, such as correlation and regression, performed on them. Scientific method_sentence_175

The measurements might be made in a controlled setting, such as a laboratory, or made on more or less inaccessible or unmanipulatable objects such as stars or human populations. Scientific method_sentence_176

The measurements often require specialized scientific instruments such as thermometers, spectroscopes, particle accelerators, or voltmeters, and the progress of a scientific field is usually intimately tied to their invention and improvement. Scientific method_sentence_177

Uncertainty Scientific method_section_18

Measurements in scientific work are also usually accompanied by estimates of their uncertainty. Scientific method_sentence_178

The uncertainty is often estimated by making repeated measurements of the desired quantity. Scientific method_sentence_179

Uncertainties may also be calculated by consideration of the uncertainties of the individual underlying quantities used. Scientific method_sentence_180

Counts of things, such as the number of people in a nation at a particular time, may also have an uncertainty due to data collection limitations. Scientific method_sentence_181

Or counts may represent a sample of desired quantities, with an uncertainty that depends upon the sampling method used and the number of samples taken. Scientific method_sentence_182

Definition Scientific method_section_19

Measurements demand the use of operational definitions of relevant quantities. Scientific method_sentence_183

That is, a scientific quantity is described or defined by how it is measured, as opposed to some more vague, inexact or "idealized" definition. Scientific method_sentence_184

For example, electric current, measured in amperes, may be operationally defined in terms of the mass of silver deposited in a certain time on an electrode in an electrochemical device that is described in some detail. Scientific method_sentence_185

The operational definition of a thing often relies on comparisons with standards: the operational definition of "mass" ultimately relies on the use of an artifact, such as a particular kilogram of platinum-iridium kept in a laboratory in France. Scientific method_sentence_186

The scientific definition of a term sometimes differs substantially from its natural language usage. Scientific method_sentence_187

For example, mass and weight overlap in meaning in common discourse, but have distinct meanings in mechanics. Scientific method_sentence_188

Scientific quantities are often characterized by their units of measure which can later be described in terms of conventional physical units when communicating the work. Scientific method_sentence_189

New theories are sometimes developed after realizing certain terms have not previously been sufficiently clearly defined. Scientific method_sentence_190

For example, Albert Einstein's first paper on relativity begins by defining simultaneity and the means for determining length. Scientific method_sentence_191

These ideas were skipped over by Isaac Newton with, "I do not define time, space, place and motion, as being well known to all." Scientific method_sentence_192

Einstein's paper then demonstrates that they (viz., absolute time and length independent of motion) were approximations. Scientific method_sentence_193

Francis Crick cautions us that when characterizing a subject, however, it can be premature to define something when it remains ill-understood. Scientific method_sentence_194

In Crick's study of consciousness, he actually found it easier to study awareness in the visual system, rather than to study free will, for example. Scientific method_sentence_195

His cautionary example was the gene; the gene was much more poorly understood before Watson and Crick's pioneering discovery of the structure of DNA; it would have been counterproductive to spend much time on the definition of the gene, before them. Scientific method_sentence_196

DNA-characterizations Scientific method_section_20

The history of the discovery of the structure of DNA is a classic example of the elements of the scientific method: in 1950 it was known that genetic inheritance had a mathematical description, starting with the studies of Gregor Mendel, and that DNA contained genetic information (Oswald Avery's transforming principle). Scientific method_sentence_197

But the mechanism of storing genetic information (i.e., genes) in DNA was unclear. Scientific method_sentence_198

Researchers in Bragg's laboratory at Cambridge University made X-ray diffraction pictures of various molecules, starting with crystals of salt, and proceeding to more complicated substances. Scientific method_sentence_199

Using clues painstakingly assembled over decades, beginning with its chemical composition, it was determined that it should be possible to characterize the physical structure of DNA, and the X-ray images would be the vehicle. Scientific method_sentence_200

..2. Scientific method_sentence_201 DNA-hypotheses Scientific method_sentence_202

Another example: precession of Mercury Scientific method_section_21

The characterization element can require extended and extensive study, even centuries. Scientific method_sentence_203

It took thousands of years of measurements, from the Chaldean, Indian, Persian, Greek, Arabic and European astronomers, to fully record the motion of planet Earth. Scientific method_sentence_204

Newton was able to include those measurements into consequences of his laws of motion. Scientific method_sentence_205

But the perihelion of the planet Mercury's orbit exhibits a precession that cannot be fully explained by Newton's laws of motion (see diagram to the right), as Leverrier pointed out in 1859. Scientific method_sentence_206

The observed difference for Mercury's precession between Newtonian theory and observation was one of the things that occurred to Albert Einstein as a possible early test of his theory of General relativity. Scientific method_sentence_207

His relativistic calculations matched observation much more closely than did Newtonian theory. Scientific method_sentence_208

The difference is approximately 43 arc-seconds per century. Scientific method_sentence_209

Hypothesis development Scientific method_section_22

Main article: Hypothesis formation Scientific method_sentence_210

A hypothesis is a suggested explanation of a phenomenon, or alternately a reasoned proposal suggesting a possible correlation between or among a set of phenomena. Scientific method_sentence_211

Normally hypotheses have the form of a mathematical model. Scientific method_sentence_212

Sometimes, but not always, they can also be formulated as existential statements, stating that some particular instance of the phenomenon being studied has some characteristic and causal explanations, which have the general form of universal statements, stating that every instance of the phenomenon has a particular characteristic. Scientific method_sentence_213

Scientists are free to use whatever resources they have – their own creativity, ideas from other fields, inductive reasoning, Bayesian inference, and so on – to imagine possible explanations for a phenomenon under study. Scientific method_sentence_214

Albert Einstein once observed that "there is no logical bridge between phenomena and their theoretical principles." Scientific method_sentence_215

Charles Sanders Peirce, borrowing a page from Aristotle (Prior Analytics, 2.25) described the incipient stages of inquiry, instigated by the "irritation of doubt" to venture a plausible guess, as abductive reasoning. Scientific method_sentence_216

The history of science is filled with stories of scientists claiming a "flash of inspiration", or a hunch, which then motivated them to look for evidence to support or refute their idea. Scientific method_sentence_217

Michael Polanyi made such creativity the centerpiece of his discussion of methodology. Scientific method_sentence_218

William Glen observes that Scientific method_sentence_219

In general scientists tend to look for theories that are "elegant" or "beautiful". Scientific method_sentence_220

Scientists often use these terms to refer to a theory that is in accordance with the known facts, but is nevertheless relatively simple and easy to handle. Scientific method_sentence_221

Occam's Razor serves as a rule of thumb for choosing the most desirable amongst a group of equally explanatory hypotheses. Scientific method_sentence_222

To minimize the confirmation bias which results from entertaining a single hypothesis, strong inference emphasizes the need for entertaining multiple alternative hypotheses. Scientific method_sentence_223

DNA-hypotheses Scientific method_section_23

Linus Pauling proposed that DNA might be a triple helix. Scientific method_sentence_224

This hypothesis was also considered by Francis Crick and James D. Watson but discarded. Scientific method_sentence_225

When Watson and Crick learned of Pauling's hypothesis, they understood from existing data that Pauling was wrong and that Pauling would soon admit his difficulties with that structure. Scientific method_sentence_226

So, the race was on to figure out the correct structure (except that Pauling did not realize at the time that he was in a race) ..3. Scientific method_sentence_227

DNA-predictions Scientific method_sentence_228

Predictions from the hypothesis Scientific method_section_24

Main article: Prediction in science Scientific method_sentence_229

Any useful hypothesis will enable predictions, by reasoning including deductive reasoning. Scientific method_sentence_230

It might predict the outcome of an experiment in a laboratory setting or the observation of a phenomenon in nature. Scientific method_sentence_231

The prediction can also be statistical and deal only with probabilities. Scientific method_sentence_232

It is essential that the outcome of testing such a prediction be currently unknown. Scientific method_sentence_233

Only in this case does a successful outcome increase the probability that the hypothesis is true. Scientific method_sentence_234

If the outcome is already known, it is called a consequence and should have already been considered while formulating the hypothesis. Scientific method_sentence_235

If the predictions are not accessible by observation or experience, the hypothesis is not yet testable and so will remain to that extent unscientific in a strict sense. Scientific method_sentence_236

A new technology or theory might make the necessary experiments feasible. Scientific method_sentence_237

For example, while a hypothesis on the existence of other intelligent species may be convincing with scientifically based speculation, there is no known experiment that can test this hypothesis. Scientific method_sentence_238

Therefore, science itself can have little to say about the possibility. Scientific method_sentence_239

In the future, a new technique may allow for an experimental test and the speculation would then become part of accepted science. Scientific method_sentence_240

DNA-predictions Scientific method_section_25

James D. Watson, Francis Crick, and others hypothesized that DNA had a helical structure. Scientific method_sentence_241

This implied that DNA's X-ray diffraction pattern would be 'x shaped'. Scientific method_sentence_242

This prediction followed from the work of Cochran, Crick and Vand (and independently by Stokes). Scientific method_sentence_243

The Cochran-Crick-Vand-Stokes theorem provided a mathematical explanation for the empirical observation that diffraction from helical structures produces x shaped patterns. Scientific method_sentence_244

In their first paper, Watson and Crick also noted that the double helix structure they proposed provided a simple mechanism for DNA replication, writing, "It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material". Scientific method_sentence_245

..4. Scientific method_sentence_246

DNA-experiments Scientific method_sentence_247

Another example: general relativity Scientific method_section_26

Einstein's theory of general relativity makes several specific predictions about the observable structure of space-time, such as that light bends in a gravitational field, and that the amount of bending depends in a precise way on the strength of that gravitational field. Scientific method_sentence_248

Arthur Eddington's observations made during a 1919 solar eclipse supported General Relativity rather than Newtonian gravitation. Scientific method_sentence_249

Experiments Scientific method_section_27

Main article: Experiment Scientific method_sentence_250

Once predictions are made, they can be sought by experiments. Scientific method_sentence_251

If the test results contradict the predictions, the hypotheses which entailed them are called into question and become less tenable. Scientific method_sentence_252

Sometimes the experiments are conducted incorrectly or are not very well designed when compared to a crucial experiment. Scientific method_sentence_253

If the experimental results confirm the predictions, then the hypotheses are considered more likely to be correct, but might still be wrong and continue to be subject to further testing. Scientific method_sentence_254

The experimental control is a technique for dealing with observational error. Scientific method_sentence_255

This technique uses the contrast between multiple samples (or observations) under differing conditions to see what varies or what remains the same. Scientific method_sentence_256

We vary the conditions for each measurement, to help isolate what has changed. Scientific method_sentence_257

Mill's canons can then help us figure out what the important factor is. Scientific method_sentence_258

Factor analysis is one technique for discovering the important factor in an effect. Scientific method_sentence_259

Depending on the predictions, the experiments can have different shapes. Scientific method_sentence_260

It could be a classical experiment in a laboratory setting, a double-blind study or an archaeological excavation. Scientific method_sentence_261

Even taking a plane from New York to Paris is an experiment that tests the aerodynamical hypotheses used for constructing the plane. Scientific method_sentence_262

Scientists assume an attitude of openness and accountability on the part of those conducting an experiment. Scientific method_sentence_263

Detailed record-keeping is essential, to aid in recording and reporting on the experimental results, and supports the effectiveness and integrity of the procedure. Scientific method_sentence_264

They will also assist in reproducing the experimental results, likely by others. Scientific method_sentence_265

Traces of this approach can be seen in the work of Hipparchus (190–120 BCE), when determining a value for the precession of the Earth, while controlled experiments can be seen in the works of Jābir ibn Hayyān (721–815 CE), al-Battani (853–929) and Alhazen (965–1039). Scientific method_sentence_266

DNA-experiments Scientific method_section_28

Watson and Crick showed an initial (and incorrect) proposal for the structure of DNA to a team from Kings College – Rosalind Franklin, Maurice Wilkins, and Raymond Gosling. Scientific method_sentence_267

Franklin immediately spotted the flaws which concerned the water content. Scientific method_sentence_268

Later Watson saw Franklin's detailed X-ray diffraction images which showed an X-shape and was able to confirm the structure was helical. Scientific method_sentence_269

This rekindled Watson and Crick's model building and led to the correct structure. Scientific method_sentence_270

..1. Scientific method_sentence_271 DNA-characterizations Scientific method_sentence_272

Evaluation and improvement Scientific method_section_29

The scientific method is iterative. Scientific method_sentence_273

At any stage, it is possible to refine its accuracy and precision, so that some consideration will lead the scientist to repeat an earlier part of the process. Scientific method_sentence_274

Failure to develop an interesting hypothesis may lead a scientist to re-define the subject under consideration. Scientific method_sentence_275

Failure of a hypothesis to produce interesting and testable predictions may lead to reconsideration of the hypothesis or of the definition of the subject. Scientific method_sentence_276

Failure of an experiment to produce interesting results may lead a scientist to reconsider the experimental method, the hypothesis, or the definition of the subject. Scientific method_sentence_277

Other scientists may start their own research and enter the process at any stage. Scientific method_sentence_278

They might adopt the characterization and formulate their own hypothesis, or they might adopt the hypothesis and deduce their own predictions. Scientific method_sentence_279

Often the experiment is not done by the person who made the prediction, and the characterization is based on experiments done by someone else. Scientific method_sentence_280

Published results of experiments can also serve as a hypothesis predicting their own reproducibility. Scientific method_sentence_281

DNA-iterations Scientific method_section_30

After considerable fruitless experimentation, being discouraged by their superior from continuing, and numerous false starts, Watson and Crick were able to infer the essential structure of DNA by concrete modeling of the physical shapes of the nucleotides which comprise it. Scientific method_sentence_282

They were guided by the bond lengths which had been deduced by Linus Pauling and by Rosalind Franklin's X-ray diffraction images. Scientific method_sentence_283

..DNA Example Scientific method_sentence_284

Confirmation Scientific method_section_31

Science is a social enterprise, and scientific work tends to be accepted by the scientific community when it has been confirmed. Scientific method_sentence_285

Crucially, experimental and theoretical results must be reproduced by others within the scientific community. Scientific method_sentence_286

Researchers have given their lives for this vision; Georg Wilhelm Richmann was killed by ball lightning (1753) when attempting to replicate the 1752 kite-flying experiment of Benjamin Franklin. Scientific method_sentence_287

To protect against bad science and fraudulent data, government research-granting agencies such as the National Science Foundation, and science journals, including Nature and Science, have a policy that researchers must archive their data and methods so that other researchers can test the data and methods and build on the research that has gone before. Scientific method_sentence_288

Scientific data archiving can be done at a number of national archives in the U.S. or in the World Data Center. Scientific method_sentence_289

Models of scientific inquiry Scientific method_section_32

Main article: Models of scientific inquiry Scientific method_sentence_290

Classical model Scientific method_section_33

The classical model of scientific inquiry derives from Aristotle, who distinguished the forms of approximate and exact reasoning, set out the threefold scheme of abductive, deductive, and inductive inference, and also treated the compound forms such as reasoning by analogy. Scientific method_sentence_291

Hypothetico-deductive model Scientific method_section_34

The hypothetico-deductive model or method is a proposed description of scientific method. Scientific method_sentence_292

Here, predictions from the hypothesis are central: if you assume the hypothesis to be true, what consequences follow? Scientific method_sentence_293

If subsequent empirical investigation does not demonstrate that these consequences or predictions correspond to the observable world, the hypothesis can be concluded to be false. Scientific method_sentence_294

Pragmatic model Scientific method_section_35

See also: Pragmatic theory of truth Scientific method_sentence_295

In 1877, Charles Sanders Peirce (1839–1914) characterized inquiry in general not as the pursuit of truth per se but as the struggle to move from irritating, inhibitory doubts born of surprises, disagreements, and the like, and to reach a secure belief, belief being that on which one is prepared to act. Scientific method_sentence_296

He framed scientific inquiry as part of a broader spectrum and as spurred, like inquiry generally, by actual doubt, not mere verbal or hyperbolic doubt, which he held to be fruitless. Scientific method_sentence_297

He outlined four methods of settling opinion, ordered from least to most successful: Scientific method_sentence_298

Scientific method_ordered_list_3

  1. The method of tenacity (policy of sticking to initial belief) – which brings comforts and decisiveness but leads to trying to ignore contrary information and others' views as if truth were intrinsically private, not public. It goes against the social impulse and easily falters since one may well notice when another's opinion is as good as one's own initial opinion. Its successes can shine but tend to be transitory.Scientific method_item_3_17
  2. The method of authority – which overcomes disagreements but sometimes brutally. Its successes can be majestic and long-lived, but it cannot operate thoroughly enough to suppress doubts indefinitely, especially when people learn of other societies present and past.Scientific method_item_3_18
  3. The method of the a priori – which promotes conformity less brutally but fosters opinions as something like tastes, arising in conversation and comparisons of perspectives in terms of "what is agreeable to reason." Thereby it depends on fashion in paradigms and goes in circles over time. It is more intellectual and respectable but, like the first two methods, sustains accidental and capricious beliefs, destining some minds to doubt it.Scientific method_item_3_19
  4. The scientific method – the method wherein inquiry regards itself as fallible and purposely tests itself and criticizes, corrects, and improves itself.Scientific method_item_3_20

Peirce held that slow, stumbling can be dangerously inferior to instinct and traditional sentiment in practical matters, and that the scientific method is best suited to theoretical research, which in turn should not be trammeled by the other methods and practical ends; reason's "first rule" is that, in order to learn, one must desire to learn and, as a corollary, must not block the way of inquiry. Scientific method_sentence_299

The scientific method excels the others by being deliberately designed to arrive – eventually – at the most secure beliefs, upon which the most successful practices can be based. Scientific method_sentence_300

Starting from the idea that people seek not truth per se but instead to subdue irritating, inhibitory doubt, Peirce showed how, through the struggle, some can come to submit to truth for the sake of belief's integrity, seek as truth the guidance of potential practice correctly to its given goal, and wed themselves to the scientific method. Scientific method_sentence_301

For Peirce, rational inquiry implies presuppositions about truth and the real; to reason is to presuppose (and at least to hope), as a principle of the reasoner's self-regulation, that the real is discoverable and independent of our vagaries of opinion. Scientific method_sentence_302

In that vein he defined truth as the correspondence of a sign (in particular, a proposition) to its object and, pragmatically, not as actual consensus of some definite, finite community (such that to inquire would be to poll the experts), but instead as that final opinion which all investigators would reach sooner or later but still inevitably, if they were to push investigation far enough, even when they start from different points. Scientific method_sentence_303

In tandem he defined the real as a true sign's object (be that object a possibility or quality, or an actuality or brute fact, or a necessity or norm or law), which is what it is independently of any finite community's opinion and, pragmatically, depends only on the final opinion destined in a sufficient investigation. Scientific method_sentence_304

That is a destination as far, or near, as the truth itself to you or me or the given finite community. Scientific method_sentence_305

Thus, his theory of inquiry boils down to "Do the science." Scientific method_sentence_306

Those conceptions of truth and the real involve the idea of a community both without definite limits (and thus potentially self-correcting as far as needed) and capable of definite increase of knowledge. Scientific method_sentence_307

As inference, "logic is rooted in the social principle" since it depends on a standpoint that is, in a sense, unlimited. Scientific method_sentence_308

Paying special attention to the generation of explanations, Peirce outlined the scientific method as a coordination of three kinds of inference in a purposeful cycle aimed at settling doubts, as follows (in §III–IV in "A Neglected Argument" except as otherwise noted): Scientific method_sentence_309

Scientific method_ordered_list_4

  1. Abduction (or retroduction). Guessing, inference to explanatory hypotheses for selection of those best worth trying. From abduction, Peirce distinguishes induction as inferring, on the basis of tests, the proportion of truth in the hypothesis. Every inquiry, whether into ideas, brute facts, or norms and laws, arises from surprising observations in one or more of those realms (and for example at any stage of an inquiry already underway). All explanatory content of theories comes from abduction, which guesses a new or outside idea so as to account in a simple, economical way for a surprising or complicative phenomenon. Oftenest, even a well-prepared mind guesses wrong. But the modicum of success of our guesses far exceeds that of sheer luck and seems born of attunement to nature by instincts developed or inherent, especially insofar as best guesses are optimally plausible and simple in the sense, said Peirce, of the "facile and natural", as by Galileo's natural light of reason and as distinct from "logical simplicity". Abduction is the most fertile but least secure mode of inference. Its general rationale is inductive: it succeeds often enough and, without it, there is no hope of sufficiently expediting inquiry (often multi-generational) toward new truths. Coordinative method leads from abducing a plausible hypothesis to judging it for its testability and for how its trial would economize inquiry itself. Peirce calls his pragmatism "the logic of abduction". His pragmatic maxim is: "Consider what effects that might conceivably have practical bearings you conceive the objects of your conception to have. Then, your conception of those effects is the whole of your conception of the object". His pragmatism is a method of reducing conceptual confusions fruitfully by equating the meaning of any conception with the conceivable practical implications of its object's conceived effects – a method of experimentational mental reflection hospitable to forming hypotheses and conducive to testing them. It favors efficiency. The hypothesis, being insecure, needs to have practical implications leading at least to mental tests and, in science, lending themselves to scientific tests. A simple but unlikely guess, if uncostly to test for falsity, may belong first in line for testing. A guess is intrinsically worth testing if it has instinctive plausibility or reasoned objective probability, while subjective likelihood, though reasoned, can be misleadingly seductive. Guesses can be chosen for trial strategically, for their caution (for which Peirce gave as an example the game of Twenty Questions), breadth, and incomplexity. One can hope to discover only that which time would reveal through a learner's sufficient experience anyway, so the point is to expedite it; the economy of research is what demands the leap, so to speak, of abduction and governs its art.Scientific method_item_4_21
  2. Deduction. Two stages:Scientific method_item_4_22
    1. Explication. Unclearly premised, but deductive, analysis of the hypothesis in order to render its parts as clear as possible.Scientific method_item_4_23
    2. Demonstration: Deductive argumentation, Euclidean in procedure. Explicit deduction of hypothesis's consequences as predictions, for induction to test, about evidence to be found. Corollarial or, if needed, theorematic.Scientific method_item_4_24
  3. Induction. The long-run validity of the rule of induction is deducible from the principle (presuppositional to reasoning in general) that the real is only the object of the final opinion to which adequate investigation would lead; anything to which no such process would ever lead would not be real. Induction involving ongoing tests or observations follows a method which, sufficiently persisted in, will diminish its error below any predesignate degree. Three stages:Scientific method_item_4_25
    1. Classification. Unclearly premised, but inductive, classing of objects of experience under general ideas.Scientific method_item_4_26
    2. Probation: direct inductive argumentation. Crude (the enumeration of instances) or gradual (new estimate of proportion of truth in the hypothesis after each test). Gradual induction is qualitative or quantitative; if qualitative, then dependent on weightings of qualities or characters; if quantitative, then dependent on measurements, or on statistics, or on countings.Scientific method_item_4_27
    3. Sentential Induction. "... which, by inductive reasonings, appraises the different probations singly, then their combinations, then makes self-appraisal of these very appraisals themselves, and passes final judgment on the whole result".Scientific method_item_4_28

Science of complex systems Scientific method_section_36

Science applied to complex systems can involve elements such as transdisciplinarity, systems theory and scientific modelling. Scientific method_sentence_310

The Santa Fe Institute studies such systems; Murray Gell-Mann interconnects these topics with message passing. Scientific method_sentence_311

In general, the scientific method may be difficult to apply stringently to diverse, interconnected systems and large data sets. Scientific method_sentence_312

In particular, practices used within Big data, such as predictive analytics, may be considered to be at odds with the scientific method. Scientific method_sentence_313

Communication and community Scientific method_section_37

See also: Scientific community and Scholarly communication Scientific method_sentence_314

Frequently the scientific method is employed not only by a single person but also by several people cooperating directly or indirectly. Scientific method_sentence_315

Such cooperation can be regarded as an important element of a scientific community. Scientific method_sentence_316

Various standards of scientific methodology are used within such an environment. Scientific method_sentence_317

Peer review evaluation Scientific method_section_38

Scientific journals use a process of peer review, in which scientists' manuscripts are submitted by editors of scientific journals to (usually one to three, and usually anonymous) fellow scientists familiar with the field for evaluation. Scientific method_sentence_318

In certain journals, the journal itself selects the referees; while in others (especially journals that are extremely specialized), the manuscript author might recommend referees. Scientific method_sentence_319

The referees may or may not recommend publication, or they might recommend publication with suggested modifications, or sometimes, publication in another journal. Scientific method_sentence_320

This standard is practiced to various degrees by different journals, and can have the effect of keeping the literature free of obvious errors and to generally improve the quality of the material, especially in the journals who use the standard most rigorously. Scientific method_sentence_321

The peer-review process can have limitations when considering research outside the conventional scientific paradigm: problems of "groupthink" can interfere with open and fair deliberation of some new research. Scientific method_sentence_322

Documentation and replication Scientific method_section_39

Main article: Reproducibility Scientific method_sentence_323

Sometimes experimenters may make systematic errors during their experiments, veer from standard methods and practices (Pathological science) for various reasons, or, in rare cases, deliberately report false results. Scientific method_sentence_324

Occasionally because of this then, other scientists might attempt to repeat the experiments in order to duplicate the results. Scientific method_sentence_325

Archiving Scientific method_section_40

Researchers sometimes practice scientific data archiving, such as in compliance with the policies of government funding agencies and scientific journals. Scientific method_sentence_326

In these cases, detailed records of their experimental procedures, raw data, statistical analyses and source code can be preserved in order to provide evidence of the methodology and practice of the procedure and assist in any potential future attempts to reproduce the result. Scientific method_sentence_327

These procedural records may also assist in the conception of new experiments to test the hypothesis, and may prove useful to engineers who might examine the potential practical applications of a discovery. Scientific method_sentence_328

Data sharing Scientific method_section_41

When additional information is needed before a study can be reproduced, the author of the study might be asked to provide it. Scientific method_sentence_329

They might provide it, or if the author refuses to share data, appeals can be made to the journal editors who published the study or to the institution which funded the research. Scientific method_sentence_330

Limitations Scientific method_section_42

Since it is impossible for a scientist to record everything that took place in an experiment, facts selected for their apparent relevance are reported. Scientific method_sentence_331

This may lead, unavoidably, to problems later if some supposedly irrelevant feature is questioned. Scientific method_sentence_332

For example, Heinrich Hertz did not report the size of the room used to test Maxwell's equations, which later turned out to account for a small deviation in the results. Scientific method_sentence_333

The problem is that parts of the theory itself need to be assumed in order to select and report the experimental conditions. Scientific method_sentence_334

The observations are hence sometimes described as being 'theory-laden'. Scientific method_sentence_335

Philosophy and sociology of science Scientific method_section_43

See also: Philosophy of science and Sociology of science Scientific method_sentence_336

Analytical philosophy Scientific method_section_44

Philosophy of science looks at the underpinning logic of the scientific method, at what separates science from non-science, and the ethic that is implicit in science. Scientific method_sentence_337

There are basic assumptions, derived from philosophy by at least one prominent scientist, that form the base of the scientific method – namely, that reality is objective and consistent, that humans have the capacity to perceive reality accurately, and that rational explanations exist for elements of the real world. Scientific method_sentence_338

These assumptions from methodological naturalism form a basis on which science may be grounded. Scientific method_sentence_339

Logical Positivist, empiricist, falsificationist, and other theories have criticized these assumptions and given alternative accounts of the logic of science, but each has also itself been criticized. Scientific method_sentence_340

Thomas Kuhn examined the history of science in his The Structure of Scientific Revolutions, and found that the actual method used by scientists differed dramatically from the then-espoused method. Scientific method_sentence_341

His observations of science practice are essentially sociological and do not speak to how science is or can be practiced in other times and other cultures. Scientific method_sentence_342

Norwood Russell Hanson, Imre Lakatos and Thomas Kuhn have done extensive work on the "theory-laden" character of observation. Scientific method_sentence_343

Hanson (1958) first coined the term for the idea that all observation is dependent on the conceptual framework of the observer, using the concept of gestalt to show how preconceptions can affect both observation and description. Scientific method_sentence_344

He opens Chapter 1 with a discussion of the Golgi bodies and their initial rejection as an artefact of staining technique, and a discussion of Brahe and Kepler observing the dawn and seeing a "different" sun rise despite the same physiological phenomenon. Scientific method_sentence_345

Kuhn and Feyerabend acknowledge the pioneering significance of his work. Scientific method_sentence_346

Kuhn (1961) said the scientist generally has a theory in mind before designing and undertaking experiments so as to make empirical observations, and that the "route from theory to measurement can almost never be traveled backward". Scientific method_sentence_347

This implies that the way in which theory is tested is dictated by the nature of the theory itself, which led Kuhn (1961, p. 166) to argue that "once it has been adopted by a profession ... no theory is recognized to be testable by any quantitative tests that it has not already passed". Scientific method_sentence_348

Post-modernism and science wars Scientific method_section_45

Paul Feyerabend similarly examined the history of science, and was led to deny that science is genuinely a methodological process. Scientific method_sentence_349

In his book Against Method he argues that scientific progress is not the result of applying any particular method. Scientific method_sentence_350

In essence, he says that for any specific method or norm of science, one can find a historic episode where violating it has contributed to the progress of science. Scientific method_sentence_351

Thus, if believers in scientific method wish to express a single universally valid rule, Feyerabend jokingly suggests, it should be 'anything goes'. Scientific method_sentence_352

Criticisms such as his led to the strong programme, a radical approach to the sociology of science. Scientific method_sentence_353

The postmodernist critiques of science have themselves been the subject of intense controversy. Scientific method_sentence_354

This ongoing debate, known as the science wars, is the result of conflicting values and assumptions between the postmodernist and realist camps. Scientific method_sentence_355

Whereas postmodernists assert that scientific knowledge is simply another discourse (note that this term has special meaning in this context) and not representative of any form of fundamental truth, realists in the scientific community maintain that scientific knowledge does reveal real and fundamental truths about reality. Scientific method_sentence_356

Many books have been written by scientists which take on this problem and challenge the assertions of the postmodernists while defending science as a legitimate method of deriving truth. Scientific method_sentence_357

Anthropology and sociology Scientific method_section_46

In anthropology and sociology, following the field research in an academic scientific laboratory by Latour and Woolgar, Karin Knorr Cetina has conducted a comparative study of two scientific fields (namely high energy physics and molecular biology) to conclude that the epistemic practices and reasonings within both scientific communities are different enough to introduce the concept of "epistemic cultures", in contradiction with the idea that a so-called "scientific method" is unique and a unifying concept. Scientific method_sentence_358

Role of chance in discovery Scientific method_section_47

Main article: Role of chance in scientific discoveries Scientific method_sentence_359

Somewhere between 33% and 50% of all scientific discoveries are estimated to have been stumbled upon, rather than sought out. Scientific method_sentence_360

This may explain why scientists so often express that they were lucky. Scientific method_sentence_361

Louis Pasteur is credited with the famous saying that "Luck favours the prepared mind", but some psychologists have begun to study what it means to be 'prepared for luck' in the scientific context. Scientific method_sentence_362

Research is showing that scientists are taught various heuristics that tend to harness chance and the unexpected. Scientific method_sentence_363

This is what Nassim Nicholas Taleb calls "Anti-fragility"; while some systems of investigation are fragile in the face of human error, human bias, and randomness, the scientific method is more than resistant or tough – it actually benefits from such randomness in many ways (it is anti-fragile). Scientific method_sentence_364

Taleb believes that the more anti-fragile the system, the more it will flourish in the real world. Scientific method_sentence_365

Psychologist Kevin Dunbar says the process of discovery often starts with researchers finding bugs in their experiments. Scientific method_sentence_366

These unexpected results lead researchers to try to fix what they think is an error in their method. Scientific method_sentence_367

Eventually, the researcher decides the error is too persistent and systematic to be a coincidence. Scientific method_sentence_368

The highly controlled, cautious and curious aspects of the scientific method are thus what make it well suited for identifying such persistent systematic errors. Scientific method_sentence_369

At this point, the researcher will begin to think of theoretical explanations for the error, often seeking the help of colleagues across different domains of expertise. Scientific method_sentence_370

Relationship with mathematics Scientific method_section_48

Science is the process of gathering, comparing, and evaluating proposed models against observables. Scientific method_sentence_371

A model can be a simulation, mathematical or chemical formula, or set of proposed steps. Scientific method_sentence_372

Science is like mathematics in that researchers in both disciplines try to distinguish what is known from what is unknown at each stage of discovery. Scientific method_sentence_373

Models, in both science and mathematics, need to be internally consistent and also ought to be falsifiable (capable of disproof). Scientific method_sentence_374

In mathematics, a statement need not yet be proven; at such a stage, that statement would be called a conjecture. Scientific method_sentence_375

But when a statement has attained mathematical proof, that statement gains a kind of immortality which is highly prized by mathematicians, and for which some mathematicians devote their lives. Scientific method_sentence_376

Mathematical work and scientific work can inspire each other. Scientific method_sentence_377

For example, the technical concept of time arose in science, and timelessness was a hallmark of a mathematical topic. Scientific method_sentence_378

But today, the Poincaré conjecture has been proven using time as a mathematical concept in which objects can flow (see Ricci flow). Scientific method_sentence_379

Nevertheless, the connection between mathematics and reality (and so science to the extent it describes reality) remains obscure. Scientific method_sentence_380

Eugene Wigner's paper, The Unreasonable Effectiveness of Mathematics in the Natural Sciences, is a very well known account of the issue from a Nobel Prize-winning physicist. Scientific method_sentence_381

In fact, some observers (including some well-known mathematicians such as Gregory Chaitin, and others such as Lakoff and Núñez) have suggested that mathematics is the result of practitioner bias and human limitation (including cultural ones), somewhat like the post-modernist view of science. Scientific method_sentence_382

George Pólya's work on problem solving, the construction of mathematical proofs, and heuristic show that the mathematical method and the scientific method differ in detail, while nevertheless resembling each other in using iterative or recursive steps. Scientific method_sentence_383

Scientific method_table_general_0

Scientific method_cell_0_0_0 Mathematical methodScientific method_header_cell_0_0_1 Scientific methodScientific method_header_cell_0_0_2
1Scientific method_header_cell_0_1_0 UnderstandingScientific method_cell_0_1_1 Characterization from experience and observationScientific method_cell_0_1_2
2Scientific method_header_cell_0_2_0 AnalysisScientific method_cell_0_2_1 Hypothesis: a proposed explanationScientific method_cell_0_2_2
3Scientific method_header_cell_0_3_0 Scientific method_cell_0_3_1 Deduction: prediction from the hypothesisScientific method_cell_0_3_2
4Scientific method_header_cell_0_4_0 Review/ExtendScientific method_cell_0_4_1 Test and experimentScientific method_cell_0_4_2

In Pólya's view, understanding involves restating unfamiliar definitions in your own words, resorting to geometrical figures, and questioning what we know and do not know already; analysis, which Pólya takes from Pappus, involves free and heuristic construction of plausible arguments, working backward from the goal, and devising a plan for constructing the proof; synthesis is the strict Euclidean exposition of step-by-step details of the proof; review involves reconsidering and re-examining the result and the path taken to it. Scientific method_sentence_384

Gauss, when asked how he came about his theorems, once replied "durch planmässiges Tattonieren" (through systematic palpable experimentation). Scientific method_sentence_385

Imre Lakatos argued that mathematicians actually use contradiction, criticism and revision as principles for improving their work. Scientific method_sentence_386

In like manner to science, where truth is sought, but certainty is not found, in Proofs and refutations (1976), what Lakatos tried to establish was that no theorem of informal mathematics is final or perfect. Scientific method_sentence_387

This means that we should not think that a theorem is ultimately true, only that no counterexample has yet been found. Scientific method_sentence_388

Once a counterexample, i.e. an entity contradicting/not explained by the theorem is found, we adjust the theorem, possibly extending the domain of its validity. Scientific method_sentence_389

This is a continuous way our knowledge accumulates, through the logic and process of proofs and refutations. Scientific method_sentence_390

(If axioms are given for a branch of mathematics, however, Lakatos claimed that proofs from those axioms were tautological, i.e. logically true, by rewriting them, as did Poincaré (Proofs and Refutations, 1976).) Scientific method_sentence_391

Lakatos proposed an account of mathematical knowledge based on Polya's idea of heuristics. Scientific method_sentence_392

In Proofs and Refutations, Lakatos gave several basic rules for finding proofs and counterexamples to conjectures. Scientific method_sentence_393

He thought that mathematical 'thought experiments' are a valid way to discover mathematical conjectures and proofs. Scientific method_sentence_394

Relationship with statistics Scientific method_section_49

When the scientific method employs statistics as part of its arsenal, there are mathematical and practical issues that can have a deleterious effect on the reliability of the output of scientific methods. Scientific method_sentence_395

This is described in a popular 2005 scientific paper "Why Most Published Research Findings Are False" by John Ioannidis, which is considered foundational to the field of metascience. Scientific method_sentence_396

Much research in metascience seeks to identify poor use of statistics and improve its use. Scientific method_sentence_397

The particular points raised are statistical ("The smaller the studies conducted in a scientific field, the less likely the research findings are to be true" and "The greater the flexibility in designs, definitions, outcomes, and analytical modes in a scientific field, the less likely the research findings are to be true.") Scientific method_sentence_398

and economical ("The greater the financial and other interests and prejudices in a scientific field, the less likely the research findings are to be true" and "The hotter a scientific field (with more scientific teams involved), the less likely the research findings are to be true.") Scientific method_sentence_399

Hence: "Most research findings are false for most research designs and for most fields" and "As shown, the majority of modern biomedical research is operating in areas with very low pre- and poststudy probability for true findings." Scientific method_sentence_400

However: "Nevertheless, most new discoveries will continue to stem from hypothesis-generating research with low or very low pre-study odds," which means that *new* discoveries will come from research that, when that research started, had low or very low odds (a low or very low chance) of succeeding. Scientific method_sentence_401

Hence, if the scientific method is used to expand the frontiers of knowledge, research into areas that are outside the mainstream will yield most new discoveries. Scientific method_sentence_402

See also Scientific method_section_50

Problems and issues Scientific method_section_51

History, philosophy, sociology Scientific method_section_52

Credits to the contents of this page go to the authors of the corresponding Wikipedia page: en.wikipedia.org/wiki/Scientific method.