Has there been a proven theory

The scientific progress of knowledge, criteria of validation and rejection of theories - a methodology of scientific research programs

Table of Contents

List of figures

1 Introduction

2 Scientific advances in knowledge

3 criteria for validation and rejection of theories

3.1 Criteria according to T. S. Kuhn

3.2 Criteria according to I. Lakatos

3.2.1 Dogmatic falsificationism

3.2.2 Naive methodological falsificationism

3.2.3 Refined methodological falsificationism

3.2.4 Methodology of scientific research programs

4 Summary

5 Conclusion


Bibliography Index of keywords

List of figures

Figure 1: Forms of falsificationism

Figure 2: How the negative heuristic works

Figure 3: How the positive heuristic works


Scientific progress goes hand in hand with an ever increasing number of scientific theories. New theories are constantly being put forward and old theories discarded. There are sometimes several theories to explain a certain phenomenon, the proponents of which are firmly convinced of the correctness of their own theory. The problem now is the selection of one of these theories or the setting up of your own theory with the aim of reproducing the truth - the real events - behind a certain phenomenon. But which theory should one choose? What criteria should scientists use to decide on one of the theories in order to be able to assume the correctness of their own decision with great probability in retrospect? Philosophers such as Popper, Lakatos, Kuhn and Feyerabend have thought deeply about all of these questions. Using the history of science, you have tried to analyze how certain theories have actually gained acceptance.

This work begins with the general overview of the scientific progress. It describes the way in which theses are drawn up, these theses find approval and in the course of the existence of the individual theories the attempt at falsification is made more or less successfully.

After this basic presentation of the scientific working method, the views of Kuhn and Lakatos will be discussed in detail. It is shown how these philosophers imagine scientific progress in knowledge, according to which criteria scientific theories are proven or rejected in their respective sense and how they try to substantiate their theories on the basis of the history of science.

The final consideration ultimately serves to emphasize the most important lines of thought, and in the closing words the author of this work tries to draw a conclusion for himself from the topic of this seminar paper.

Scientific progress in knowledge

A fundamental goal of science is the search for satisfactory explanations for certain events, as was already attempted in pre-scientific times through myths and cosmologies. However, a decisive step in the development of science can be described as the fact that scientific explanations can be empirically criticized, whereas myths and cosmologies are only passed on as parts of a tradition. Any scientist who puts forward a scientific theory must be open to criticism from other scientists in relation to his own theory.

"For centuries, knowledge was understood proven knowledge", ie only theories were accepted that were comprehensible with the human senses or could be explained logically at the time. Nowadays" there are only a few philosophers or scientists who are of the opinion that scientific knowledge is or could be proven knowledge . "Theories are mostly justified with other theories or assumptions that are considered probable, but of which no one can prove the correctness. The word" prove "in the previous sentence should be understood here to mean the question by which type of proof a hundred percent correctness a thesis can be proven.

It is controversial whether there is an empirical basis for science. An empirical basis should be understood as a basic stock of knowledge from which the correctness is assumed. All new theories should then be built on this empirical basis; these new theories should be able to be verified by the existing empirical basis.

In the philosophy of science there are different doctrines about the above-mentioned criticism of scientific theories and the related criteria for accepting or rejecting a theory. Many scientists assume the fallibility, i.e. the fallibility in principle, of scientific theories. Because of this, they draw up special sentences in order to be able to test theories. The sentences are also called Test sets or Basic rates denotes and represents the result of special observations or experiments. If another scientist succeeds in falsifying a certain theory through an empirical experiment, this does not necessarily mean that the previously existing theory is automatically rejected. Scientific progress in knowledge is understood by this group of scientists as a constant setting up of new hypotheses or theories or as the constant attempt to criticize theories that have been set up.

If the founder of a falsified theory is still convinced of his theory despite a counterexample, it is entirely conceivable that an auxiliary hypothesis will be set up or that the theory will be modified in some areas. A counterexample is therefore generally not yet a criterion for rejecting a scientific theory.

There is also the view among some philosophers that a new theory can prevail through appropriate persuasion. If a new theory is presented convincingly enough, it will also prevail as a common doctrine.

As an example of such theories in the history of science, the dispute over the Copernican and Ptolemaic theory is very often mentioned in the literature, i.e. over the question of whether the earth is the resting center of the universe or whether the sun takes this place. In order to defend the theory that the earth is the center of the universe, minor changes were made after each attempt at falsification, thus renewing the old theory. Another important reason for adhering to the Ptolemaic worldview was also the church, which tried to defend this worldview through propaganda for reasons of faith.

Criteria for the validation and rejection of theories

The following presentation of various doctrines is intended to give an overview of the problem of the validation and rejection of newly established theories.

Criteria according to T. S. Kuhn

Kuhn is a representative of the new philosophy of science, which does not assume that science develops cumulatively. In his opinion, there is no constant growth, no continuous setting up of new scientific theories accompanied by constant criticism and improvement of previous ones.

Kuhn contradicts the scientific theory of falsificationism, which describes a systematic examination of the empirical basis. For him there is no secure and irreversible empirical basis of science. For him, test sentences are in principle fallible, which thus raises the question of how a test sentence can falsify a theory of which it is not itself known whether it is true or false. He is of the opinion that experience itself, and thus science as well, without theoretical prejudices, i.e. without assumptions, is impossible.

Kuhn claims that in scientific experiments Gestalt perceptions play an important role. In this context he understands the term Gestalt perception the different perception or interpretation of a situation by two people. As an example, Kuhn points out that two people who look at the same picture interpret this picture completely differently, i.e. the first viewer could see a rabbit in the picture, while the second viewer thinks he sees a duck. On the basis of this knowledge, the scientists learn to see their research area with completely different eyes when discoveries or scientific revolutions have taken place.

Based on his considerations, Kuhn has developed a model of the historical development of science, which divides the scientific progress of knowledge into two areas, which are determined by the different research strategies in the "normal sciences" and the "extraordinary sciences" Marked are.

The "normal science" - also called "normal science" - is present when certain doctrines have proven themselves in solving problems that arise. In this, scientists mostly use cautious research strategies that are only characterized by small theoretical changes. Most scientists at such a time are approximately convinced of the correctness of the prevailing theory and are therefore not particularly interested in rejecting these theories. Kuhn describes this period of normal science as an attempt to solve standard problems with standard methods.

However, if anomalies accumulate or if the prevailing theories no longer prove themselves in explaining certain phenomena, scientists also lose faith in these theories and the time of "extraordinary science" arrives. This is characterized by revolutionary research strategies. He claims that scientists actually only look for new theories during this unusual time of crisis. In his opinion, the period can be characterized by three groups of features:

1. He assumes that revolutionary changes have a holistic structure. Changes of this kind are therefore not carried out step by step, but interrelated regularities are simultaneously subjected to a joint revision.
2. The second group of characteristics is characterized by a change in meaning, i.e. a change in the way in which words and sentences are connected to natural phenomena. An example here could be the discovery of a new property, such as electricity, in a certain object. This new property allows certain conclusions to be drawn for theories with which this object is connected.
3. The last characteristic he mentions is a changed feeling for what is similar or different from one another. If new knowledge is gained, then, on the basis of this knowledge, connections between different theories can be interpreted completely differently, if it is not even established that there is no connection between the theories under consideration.

This period of extraordinary science is broken off as soon as a promising doctrine has been found again, and the period of normal science begins again.

According to Kuhn, two prerequisites must be met before a scientific theory can be rejected: "(1) First, a scientific crisis must occur in order to search for completely new theories, (2) in the extraordinary research of the time of crisis a theory that appears better be set up so that the old theory may be abandoned. "

In summary, the criteria for accepting and rejecting a scientific theory according to Kuhn are psychologically conditioned. If scientists are convinced of a new theory, they accept it, but if they lose faith in a prevailing theory, it will be rejected by a scientific revolution.

I. Lakatos criteria

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Lakatos tries to defend the critical rationalism represented by Popper and the associated falsificationism against the criticism of Kuhn and at the same time developed a methodology of critical rationalism. He constructed two variants of falsificationism in order to be able to show that a reasonable and objective progress in knowledge is possible with it. Lakatos calls the first variant the dogmatic falsificationism, in which experience can prove the truth of the empirical basis of science. The latter assumption is made in the second variant - the methodological falsificationism - discarded. From methodological falsificationism, Lakatos constructs the naive and the refined methodological falsificationism, which are described in more detail below. Figure 1 gives a detailed overview of the types of falsificationism of Lakatos.

In the next few chapters, the various types of falsificationism and the resulting consequences for the progress of scientific knowledge will be examined more closely.

Dogmatic falsificationism

Lakatos seems to have developed dogmatic falsificationism because this theory reveals misunderstandings of falsificationism based on the philosophy of the foundation. In his explanations he also shows that this theory is not tenable.

Dogmatic falsificationism indicates the fallibility of all scientific theories in principle, but sticks to a kind of infallible empirical basis with which the framework of the progress of knowledge, consisting of scientific theories, is expanded. Lakatos strengthens the statement of the fallibility in principle by the statement: "The decisive characteristic of dogmatic falsificationism is the insight that all theories are equally conjectures. Science cannot prove a single theory."

For dogmatic falsificationism, scientific honesty consists in being able to specify criteria at the same time as a new theory with which this new theory can be rejected. If it is now possible to refute one of these criteria, then the "sentence must be rejected unconditionally".

Lakatos describes the scientific progress of dogmatic falsificationism as an evolutionary process: "According to the logic of dogmatic falsificationism, the growth process of science consists in the repeated rejection of theories on the basis of hard facts."

Nevertheless, dogmatic falsificationism is untenable on the basis of three facts:

1. Dogmatic falsificationism is based on the fact that there is a psychological boundary between theoretical, speculative propositions and Observational sentences exists. According to him, it should be immediately clear to every viewer which theory was created through creative speculation or on the basis of observation. This assumption is refuted by Lakatos by considering some characteristic examples of the history of science and with the help of psychology. For him there is and cannot be a perception "that is not permeated by expectations." This means that every perception is shaped by the background thoughts of the respective viewer.
2. Furthermore, dogmatic falsificationism regards as proven any theory that has been proven by mere observation. For Lakatos this assumption is untenable because of the following statement: "No factual statement can ever be proven on the basis of an experiment."
3. The last untenable fact for Lakatos is the delimitation criterion of dogmatic falsificationism, which tries to differentiate a scientific from an unscientific theory. The delimitation criterion only considers a theory to be scientific if it has an empirical basis. This fact is refuted by Lakatos through examples from the history of science.

In summary, Lakatos describes dogmatic falsificationism as a theory that reflects the knowledge that not only proven, but also unproven theories can be scientific. For unproven theories, however, it must be possible to specify criteria that reject them. In other words, any new theory that is built on the empirical basis and for which criteria can be given for rejection can be said to be scientific.

Overall, however, this theory is untenable for him. In his opinion, no reliable empirical basis can exist, since it is assumed that every scientific theory is fallible in principle.

Naive methodological falsificationism

Methodological falsificationism emerged from the assumption of a secure empirical basis for dogmatic falsificationism and the resulting criticism. Naive methodological falsificationism recognizes that the empirical basis on which a scientist builds his framework of theories is not infallible. Lakatos says: "The naive methodological falsificationism recognizes that the experimental techniques of the scientist involve fallible theories in the light of which he interprets the facts."

Although the naive methodological falsificationism assumes the fundamental fallibility of the theories in the empirical basis, it uses these theories in the development or testing of new theories as unproblematic background knowledge that is accepted as unproblematic on a trial basis.Here the successful theories are understood as an extension of the senses, which are similar to the observation strategies of dogmatic falsificationism, but which bring about a considerable expansion of a scientist's knowledge base.

Another reason to distinguish between dogmatic and naive methodological falsificationism is the interpretation of the falsification. The naive methodological falsificationism separates the Elimination and refutation a theory. Lakatos understands the elimination to mean the elimination of a theory, while in the refutation of a theory only a counterexample against this theory was found. But, in his opinion, a counterexample is by no means sufficient to completely ignore a theory. The following quote should justify his train of thought: "If a theory is falsified, then its falsehood is proven; a falsified theory can still be true."

On the basis of the consideration in the previous paragraph one can see another characteristic of naive methodological falsificationism. With regard to the type of falsificationism, the scientist has to decide which theory he accepts as unproblematic background knowledge and which he does not. It is precisely this very subjective type of decision that is very noticeable here.

In summary, one can hold onto observation as a criterion for a theory to prove itself in naive methodological falsificationism. The observation of a test set that reproduces the result of a theory must be traceable for safety reasons when an experiment is repeated several times. To further justify new theories, the theories of the empirical basis can still be used, in which, however, a fundamental fallibility cannot be ruled out.

Despite the extensions presented, this type of falsificationism cannot be maintained for Lakatos either, and he tried to replace it with a more ingenious form.

Refined methodological falsificationism

The refined methodological falsificationism builds on the considerations of the naive methodological falsificationism, but differs in some areas.

With this type of falsificationism, a theory is scientific if and only if it meets certain conditions. New theories thus prove themselves by fulfilling the following conditions:

1. The newly established theory must have a salary excess compared to a previously dominant theory. Lakatos understands that the new theory is in excess of its content as new facts or other criteria for rejection of the prevailing theory.

2. Part of the excess content of a new theory must be verified, i.e. scientifically proven.

If a theory fulfills the above two conditions, it can be described as scientific, or rather, it has been scientifically proven. This theory can only be rejected after it also fulfills a third condition.

1. The knowledge content of an old theory that is not refuted by the new theory must be found again in the new theory. So if an old theory explains a certain phenomenon, but is replaced by a new theory, the old theory is usually not complete, but only partially rejected. The sub-areas of the old theory, which are not rejected by the new theory, must be found in the newly established theory after this condition.

According to Lakatos, it is possible to use these conditions to specify objective criteria for comparing theories, and he recommends eliminating the less good theory when there is a better one. If such an elimination takes place, the theory with the greatest increase in proven content is always chosen. Refined falsificationism "allows any part of the body of science to be replaced, but only on the condition that the replacement occurs in a progressive manner and that new facts" and knowledge are gained through this modification.

In summary, Lakatos describes the advantage of refined falsificationism by extending the term theory to a series of theories, since a new theory must always cover the respective knowledge content of an old theories. Thus, there is no evaluation of individual theories, but mostly series of theories that could perhaps also be referred to as research programs. In refined falsificationism, new theories lead to a constant increase in knowledge, since new theories have to learn from the past at the same time, i.e. any content of an old theory that has not been refuted is carried over into the future.

Methodology of Scientific Research Programs

The aim of this section is to identify two types or classes of research pathways that scientists should avoid (negative heuristic), or which are usually worth following (positive heuristic). Both research paths are usually pursued with different weightings within a research program.

Negative heuristic:

Figure 2 graphically describes the research path of a negative heuristic. In Lakato's opinion, any research program can go through the hard core be characterized. This hard core is from a protective belt of Auxiliary hypotheses surrounded in the graphic as an outer circle

is shown. The theory is criticized by Anomalies or Counterexamples, which are represented by the arrows. It is important to defend the hard core by constantly developing new auxiliary hypotheses, i.e. for each counterexample, a new auxiliary hypothesis is developed that invalidates it. Every anomaly is included in the protective belt, so to speak.

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A research program can be considered successful under this strategy if all of this leads to a further development of the initial theory.

Positive heuristic:

If a scientist proceeds according to the procedure of a positive heuristic - at least if he assigns the greatest weight to this procedure - then he has a goal or a vision for the future in mind, which he is trying to prove with his theory. Figure 3 tries to illustrate this situation graphically.

In pursuit of his goal, the scientist begins to develop a new theory. This point is the starting point of the elongated arrow. In the course of time this theory is attempted to be refuted by counterexamples that more or less deeply shake the theory that has been put forward. The scientist tries to eliminate the counterexamples and anomalies by setting up auxiliary hypotheses or by using new theories or models. It may even happen that he does not accept a criticism at all. But in all of this, the scientist never loses sight of his primary goal. Lakatos describes the positive heuristic approach as one that advances with almost no consideration for refutations.


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First of all, a brief insight into the scientific progress was given in this work. During this insight, various doctrines of the progress of knowledge were mentioned without going into detail. It describes the initial progress of scientific knowledge as an accumulation of proven knowledge. Over time, most scientists have broken away from the view that only proven knowledge or proven theories can count as scientific.

The third chapter deals with the actual problem of this seminar paper. Here various doctrines of criteria for the validation and rejection of scientific theories are described.

The first philosophical doctrine about scientific progress in knowledge is that of Kuhn. Kuhn divides the times of scientific research into two parts. The first part, normal science, is characterized by no significant scientific progress. During this time only proven theories are used. The second part that Kuhn describes is that of extraordinary science. This period is marked by scientific revolutions brought about by the dissatisfaction of scientists with the prevailing theories.

The second doctrine considered is from Lakatos. Different ways of looking at falsificationism are shown here. Lakatos divides falsificationism into dogmatic falsificationism and methodological falsificationism. Lakatos further divides methodological falsificationism into naive and refined methodological falsificationism. The dogmatic falsificationism is characterized by its solid empirical basis, the naive methodological falsificationism already recognizes a fundamental fallibility of the empirical basis and the refined falsificationism completes the discussion in that a new theory must always contain the content of knowledge of an old theory.

The discussion is concluded with a methodology of scientific research programs from Lakatos. He divides these procedures into a class that a scientist should use and names it positive heuristic. Scientists should avoid the second class as much as possible, which is why he calls it negative heuristic.

Final word

A final evaluation of the work produced is extremely difficult. Initially, the shock at the confused and incomprehensible text as a starting point was deep. But after using the dictionary of foreign words, an understanding of the underlying problem gradually developed and an unexpected interest was aroused.

In my opinion, one can draw the conclusion from the literature that any scientific theory is valid only until it is refuted. No theory ever put forward is truly perfect, and all evidence is only relative. For me, this shows that you have to be open to new things and that tried and tested old things should not simply be thrown overboard.


Geocentric system

geographic system, a world view in which the earth forms the resting center of the universe, especially the planetary system (including the sun and moon) (e.g.) B. in Aristotle, Ptolemy and T.) Brahe).

Heliocentric system

Heliozántric system, a world view in which the planets orbit the sun, but this still represents the center of the world. This heliocentr. Planetary theory was published in 1543 by N. Copernicus, who thus went back to thoughts that Aristarchus of Samos had in 265 BC. had expressed. The h. S. only slowly supplanted the geocentric system, but this was not only due to the resistance of the church. Only J. Kepler could with his planetary laws the weaknesses of the h.) S. correct.

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Copernicus opÁrnikus, Nicholas

(Coppernicus, Copernicus), eigtl. Nikolaus Koppernigk (Polish Kopernik), *) Thorn 19.2. 1473, †) Frauenburg (East Prussia) May 24. 1543, astronomer. K. realized that the geocentric system was unsuitable for predicting planetary positions over long periods of time. He developed the heliocentric system in which he described the annual movement of the earth around the sun and explained the daily rotation of the fixed star sky as the rotation of the earth around its own axis.

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Põpper, Sir (since 1964) Karl [Raimund], *) Vienna 28.) 7. 1902, †) London 17.) 9. 1994, British philosopher and science logician of Austrian origin. Since 1949 Professor of Logic and Philosophy of Science in London; Founder of the critical rationalismwho on the lied. The principle of permanent error correction (falsification) in the formation of theories is based, insofar as criticism of all forms of historicism (›Das Elend des Historicism‹, 1957) and social utopianism.


Logic of Research (1935), Objective Knowledge. An evolutionary draft (1972), The two basic problems of epistemology (created 1930-33, ed. 1979), The I and its brain (1982).


Ptolemy, Claudius (Ptolemaeus), *) Ptolemais around 100, †) Canopus (?) After 160, astronomer, mathematician and geographer in Alexandria. With his main work conveying the geocentric system (in Latin translation ›Almagest‹ gen.) He put the first systemat. Working out the math. Astronomy before. The second large script of P. conveys mathematics. Knowledge of determining the latitude and longitude of places.


- Andersson, Gunnar (1988): Critique and the History of Science. Tubingen
- Kuhn, S. Thomas (1984): What are scientific revolutions ?, Second edition
- Lakatos, Imre (1974): "Falsification and the methodology of scientific research programs", in "Critique and Knowledge Progress", by I. Lakatos / A. Musgrave (1974), Vieweg, Braunschweig, pp.89-190
- Meyers Lexikon (1995): on CD-ROM "LexiRom", Microsoft Corporation and Bibliographisches Institut & F.A. Brockhaus AG

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