Falsificationism
falsificationism or critical rationalism is an epistemological current founded by the Austrian philosopher Karl Popper (1902-1994). For Popper, testing a theory means trying to refute it by means of a counterexample. If it is not possible to refute it, said theory is "corroborated", and can be provisionally accepted, but not verified; that is, no theory is absolutely true, but at most "unrefuted." Falsificationism is one of the pillars of the scientific method.
The philosopher Karl Popper understood that the philosophers of the Vienna Circle (to which he himself was closely linked, although not as a member) had mixed up two different problems for which they had resolved to give a single solution: verificationism. Contrary to this view, Popper remarked that a theory might well have meaning without being scientific, and that, as such, a "significance criterion" might not necessarily coincide with a "boundary criterion." Thus, he devised his own system, which he calls falsificationism (it should be noted that Popper does not call his methodology falsificationism, but critical rationalism). This is not only interpretable as an alternative to verificationism; it also supposes an agreement about the conceptual distinction that previous theories had ignored.
For Popper —and unlike the Vienna Circle— science is not capable of verifying if a hypothesis is true, but it can show if it is false. That is why induction is useless, because no matter how much you experiment you will never be able to examine all possible cases, and a single counterexample is enough to demolish a theory. Thus, against the preponderant verificationist position up to that moment in the philosophy of science, Popper proposes falsificationism. Although Popper was a realist, he did not accept certainty, that is, one can never know when our knowledge is certain. Popper began describing science, but in his philosophical evolution he ended up being prescriptive (although without reaching the normative rigor of the Circle), recommending the hypothetical deductive method to science. In other words, science does not make certain statements based on data, but rather proposes hypotheses (which, although based on experience, tend to go beyond experience and predict new experiences) that are then subjected to the experimental filter to detect errors.
Popper saw demarcation as a central problem in the philosophy of science. He proposed falsificationism as a way to determine if a theory is scientific or not. Simplifying, according to Karl Popper it could be said that if a theory is falsifiable, then it is scientific; if it is not falsifiable, then it is not science.
For Popper, affirming that a theory is scientific means that it adds rational knowledge about the empirical world, therefore, it cannot be:
- Tautological (does not add anything)
- Contradictory (against rational logic)
- Metaphysics (requires something that cannot be tested experimentally)
Falsifiability was one of the criteria used by Judge William Overton to determine that creationism was not scientific and should not be taught in Arkansas schools.
Falsifiability is a property of statements and theories, and is itself neutral. As a demarcation criterion, Popper seeks to take this property as a basis to affirm the superiority of falsifiable theories over non-falsifiable ones, as part of science, thus establishing a position that could be called falsificationism with political implications. [citation needed] However, many things that can be considered meaningful and useful are not falsifiable. Certainly nonfalsifiable statements play a role in scientific theories themselves. What the Popperian criterion allows to be called scientific is open to interpretation. A strict interpretation would concede very little, since there are no relevant scientific theories that are completely free of anomalies. Similarly, if we only consider the falsifiability of a theory and not the willingness of an individual or a group to obtain or accept falsifiable instances, then we would allow almost any theory.
In any case, knowing whether a statement of a theory is falsifiable is very useful, if only for the fact that it gives us insight into the ways in which someone might evaluate a theory.
The Duhem-Quine thesis argues that it is not possible to prove that a statement has been falsified; instead, falsification occurs when the scientific community agrees that it has been falsified (see scientific consensus). This is an important criticism of falsificationism, since any observational statement, however innocent it may seem, presupposes certain conceptions about the world, and it is impossible not to wonder if these conceptions are scientific or not.
Falsificationism, in each and every one of its many forms, is an interesting idea, but insufficient to characterize what science is or to solve the demarcation problem. It suffers from a number of logical and epistemological difficulties that should give us pause if we are seeking an answer as to what is good science and what is not.
From verificationism to falsificationism
Within methodological falsificationism, one can differentiate between Popper's naive initial falsificationism, the sophisticated falsificationism of Popper's late work, and the methodology of Imre Lakatos' research programs.
The problem of induction arises from the fact that something universal cannot be affirmed from the particular data offered by experience. No matter how many millions of black crows are seen, it will not be possible to say that "all crows are black." On the other hand, it is enough to find a single crow that is not black to be able to affirm: "Not all crows are black." For this reason Popper introduces falsificationism as a scientific demarcation criterion.
Popper actually rejects verificationism as a theory validation method. His central thesis is that there can be no ultimate scientific statements, that is, statements that cannot be verified or refuted from experience. Experience remains the distinctive method that characterizes empirical science and distinguishes it from other theoretical systems.
For Popper there are neither unquestionable starting points nor does scientific rationality require them. The question of truth is therefore a question of the method of seeking it and the method of recognizing falsehood. Although science is inductive in the first instance, the most important aspect is the deductive part. Science is characterized by being rational, and rationality resides in the process by which we criticize and replace, or not, our beliefs. Faced with the problem of induction, Popper proposes a series of methodological rules that allow us to decide when we should reject a hypothesis.
Popper proposes a scientific method of conjecture by which observable consequences are deduced and tested. If the consequence fails, the hypothesis is disproved and must then be rejected. Otherwise, if everything is verified, the process is repeated considering other deductible consequences. When a hypothesis has survived various refutation attempts, it is said to be corroborated, but this does not allow us to affirm that it has been definitively confirmed, but only provisionally, by empirical evidence.
Falsificationist Method
For the falsificationists, the scientist is an artist insofar as he must boldly propose a theory that will then be subjected to rigorous experiments and observations. The advance in science is in falsifying successive theories so that, knowing what it is not, we can get closer and closer to what it is.
The hypotheses proposed by falsificationists must be falsifiable, that is, they can be tested and disproved by facts or by an adverse experiment. To meet this condition, the hypotheses must be as general as possible and as clear and precise as possible. A falsifiable hypothesis would not be "tomorrow it may rain", since in no case can it be falsified ("tomorrow it may not rain").
A falsifiable hypothesis would be "the planet Mercury revolves in an orbit". A more general hypothesis (and therefore more falsifiable) would be "all planets revolve in an orbit". And a more precise hypothesis (and therefore also more falsifiable) would be "all planets revolve in an elliptical orbit".
Falsificationists always prefer hypotheses or theories that are more falsifiable, that is, more likely to be proven false, as long as they have not already been falsified. Thus science would progress based on trial and error.
A theory will be considered falsifiable when its basic statements —referring to observable events— can be divided precisely into two non-empty subclasses: that of all the basic statements with which it is in contradiction —that state what it excludes or prohibits—, its potential falsifiers, and that of all the statements with which it is not in contradiction —those that state what it allows—.
Criticism
The philosopher of science William Herbert Newton-Smith expresses his criticism as follows:
...for Popper, by accepting the most modest of the statements of observation we are implicitly accepting some theory, and we cannot feel more justified by believing in an observational statement than in the relevant theoretical statements.Newton-Smith, The rationality of science
Sophisticated counterfeiting
Sophisticated falsehoodism is the name that Imre Lakatos gives to his criticism of epistemology and falsehoodism, based on what he calls scientific research programs.
The methodology of research programmes is a step further in falsehood as it solves some of its problems. Because of this, Lakatos passes to name naive falsehoodism defended by Karl Popper in his book The logic of scientific research, while calling sophisticated fakeism to Popper's later suggestions, as well as his own research program methodology.
Lakatos tried to adapt the Popper system to the new situation created by Thomas Kuhn. Popper's intention was to make a rational reconstruction of the history of science that shows that it progresses rationally. However, the history of science shows that science does not advance only by falseing theories with facts, but that it is necessary to take into account the competition between theories and the confirmation of theories. That's why Lakatos substitutes Popper's naive fakeism for sophisticated fakeism. In reality science does not evaluate an isolated theory, but a set of theories that make up what Lakatos calls a scientific research program (also called a paradigm). A research program is completely rejected when a superior substitute is available to explain everything that explained the previous plus other additional facts. Lakatos recognizes that the difficulty of this scheme is that, in practice, it may take years to carry out it, or even be inapplicable in very complex research programs.Duhem-Quine Thesis
The thesis of Duhem-Quine (or, more broadly, confirmational holism) states that it is impossible to test in isolation a scientific hypothesis, because an empirical experiment requires assuming as certain one or more auxiliary hypothesis (also called background assumptions - background assumptions). The hypothesis in question is incapable of making predictions. In fact, the consequences of the hypothesis typically lie in the auxiliary hypothesis of which predictions derive. The above prevents a theory from coming in conclusively false through empirical meanings if the auxiliary hypothesis is not proven (since the auxiliary hypothesis sometimes includes one or more scientific theories). In such a way, to disprove the idea that the Earth was moving some noticed that the birds were not altered in the sky when they embarked on the flight from the branches of the trees. This fact is no longer accepted as empirical evidence to refute the movement of the earth because physics has adopted a system other than hypothesis that allows to make different predictions[chuckles]required].
Thus, according to this thesis
"given enough imagination, any theory (consistent in one or a finite set of propositions) can be permanently saved from "refutation" by means of an appropriate fit in the context of the knowledge that contains it"Imre Lakatos