Scientific Method: Progress, Limits, and Confirmation
Progress and Limits of Science
The problems we have seen about the scientific method call into question the naive scientism that sees science as the most perfect achievement of human rationality. This position secured an advance, estimated indefinite and unlimited scientific progress. In addition, it judges scientific principles as unquestionable dogmas, instead of theories useful and effective, but probable and provisional.
Consider two of the most important positions on this question:
- Karl Popper: The Continuous Progress of Science. For falsificationists, such as Popper, no theory can be considered true because in the future it could be falsified. However, science progresses because each new theory is closer to the truth. When a theory replaces another that has been falsified and rejected, we will consider it better than the previous one because it is more explanatory, has fewer problems, and therefore is closer to the truth. For Popper, falsifying a theory is not a bad thing because knowing its weaknesses and problems helps us make a better one. Thus, we learn from our mistakes, which ensures continued progress towards the truth, although this may, in fact, be unattainable.
- Thomas Kuhn: Scientific Revolutions. This philosopher, an expert on the history of science, has criticized the continuing and progressive version of the falsificationists. If we analyze the historical development of science, one realizes that false theories are often not abandoned and replaced by better ones, as Popper said. In the scientific paradigm of a given moment, there are numerous anomalies that do not make that theory abandoned. However, when certain special conditions are met, these anomalies can cause a crisis that leads to a scientific revolution, that is, it can cause a complete change from a paradigm in crisis to a new one. This is what happened in the 16th century with the Copernican revolution. However, we should not interpret the revolutionary change as progress, since there are no logical reasons to consider one paradigm better than the other; they are distinct and unique ways of viewing reality.
After what we’ve seen, it is clear that we must reject scientism forecasting unlimited progress of science. However, we cannot fall into relativism or skepticism that exaggerate questioning all scientific discoveries. Certainly, the tests and trials to which scientific hypotheses are subjected make science the only alternative that offers a reasonable explanation of natural and human phenomena. Therefore, we aim at a fair middle ground between naive optimism and pessimism, defeatism, and the best way to do this is to maintain a critical and humble attitude towards science.
The Scientific Method
The purpose of scientific activity is to produce safe and reliable knowledge of reality, but what guarantees its reliability? Is it really that reliable?
The more specialized a science, the greater the distance between the language that is used and a common language. Science creates an artificial language to ensure objectivity and accuracy of its concepts, laws, and theories:
- Concepts: They are the specific terms of each science.
- Laws: They are basic statements of scientific knowledge characterized by using concepts that have been previously defined in a precise and universal way to identify a regularity of nature, i.e., to explain all phenomena of the same class.
- Theories: As science seeks to explain aspects of reality as wide as possible, scientific laws are interconnected, forming coherent and systematic compact systems called scientific theories.
Method means path. A method is a more or less fixed and stable procedure, consisting of several steps or rules that allow an end. There have always been different views about the method used by scientists.
Deductive Method
It involves extracting data from general to a particular conclusion. The validity of this method is unquestionable, and the conclusion is already implicit in the data base; if they are true, the conclusion will be also. However, this method presents a problem: it is only feasible in the formal sciences.
Inductive Method
It is to draw general conclusions from particular data. After observing what happens in many cases, we believe that it will always occur to those of the same type. It is a form of generalization (moving from concrete to general).
It has a great advantage: it provides principles or laws applicable to all events of the same type. However, it presents serious problems:
- It is questionable whether, indeed, the scientific procedure begins with a neutral observation, but rather it seems that scientists rely on observation with a specific purpose, with a preconceived idea of what they are looking for.
- It is also questionable about the validity or reliability of the principles reached. In many cases, we have checked, and they are well selected, nothing assures us that all others are of the same type and even less that future cases will also follow the same pattern. This method does not provide security, but probability.
Formulation, Contrast, and Confirmation of Hypotheses
a) Hypothesis: A hypothesis is an assumption about what happens in the world and its causes. However, the method does not provide a hypothesis about the concept, how it happens to the scientist. It is not unreasonable to say that in the formulation of hypotheses, factors come into play that may seem unscientific: imagination, invention, luck, chance…
Some thinkers, such as Paul Feyerabend, extend the influence of the imagination to the whole scientific process. The revolutionary discoveries of modern science are made possible by the freedom and spontaneity displayed by the scientists. Moreover, constraining their activities to a series of fixed steps in science would become something dogmatic and sterile. And, for Feyerabend, it is an illusion to think that scientific discoveries are the result of a particular method.
b) Contrasting and Confirmation of Hypothesis: Although the formulation of hypotheses assumes a certain amount of imagination and luck, for the suggested explanation to be accepted, it must be checked with the utmost scientific rigor. However, the hypotheses in the hypothetical-deductive method are as problematic as it was in the inductive method: how many cases must we check to support a hypothesis to be true?
The philosopher Karl Popper proposed falsification as a response to this question and as an alternative to verification.
- Verification: This involves the verification of the truth of a hypothesis. To do so, see if what the hypothesis says actually happens, and if so, it will be confirmed by matching the facts. However, the only way to do this is by induction, and we have seen that it detonated only chance because it is possible that, in the future, counterexamples may appear.
- Falsification: It was proposed by Karl Popper as an alternative to the verification problem. It consists in testing the hypothesis, seeking facts to show that it is false. While not found, the hypothesis is provisionally considered true. By the time we discover a single case that is opposed to the hypothesis, it is falsified and is therefore rejected.
When a hypothesis has been proven and has not been falsified (not found a single fact that opposes it), we consider the hypothesis a scientific law, and therefore support it temporarily (until a new observation requires us to reject it).
According to falsifiability, the scientific laws are not characterized by their undoubtedly true, but by virtue of being falsifiable or refutable, i.e., which of them is possible to derive predictions risky to expose them to the error.