In the 20th century, the philosophy of science developed through various theories and debates, including logical positivism and Karl Popper’s disprovationalism. Logical positivism emphasizes verifiability, while disprovationalism emphasizes the disprovability of scientific theories. Each theory has contributed to scientific progress, but neither has provided a perfect solution. Science is constantly evolving through criticism and verification.
The 20th century was a golden age for science, with many scientific advances. The philosophy of science, which arose out of the discussion of the natural sciences, was a major contributor to all of these advances. The philosophy of science in the 20th century has been characterized by fierce debates about science, from the logical positivists to Karl Popper, Thomas Kuhn, Lacatoche, FireAvent, and others. In general, the history of philosophy of science is often divided into ‘pre-Kuhn’ and ‘post-Kuhn’ based on Thomas Kuhn, who introduced the concept of ‘structure of scientific revolutions’ or ‘paradigm’ to the world. In this article, I will introduce the modern philosophy of science from the pre-Thomas Kuhnian, logical positivist view of science to inductivism and disprovationalism, compare the characteristics of inductivism and disprovationalism, and examine the problems and limitations of these two theories.
Logical positivists criticized the inability of conventional philosophers to analyze philosophical discourse logically and insisted on using precise language. They wanted the meaning of a proposition to be determined only by the way in which it can be determined to be true or false, and they used verifiability as a criterion of meaning, categorizing unverifiable statements as meaningless. They used this criterion to categorize scientific propositions as meaningful and metaphysical or ethical propositions as meaningless. The logical positivists argued that experience is the only way to determine the truth of a proposition, and therefore the only way to determine whether a proposition is meaningful or not. Logical positivists propose inductivism and hypothetic deduction as methods of empirical judgment.
Inductive reasoning is a process of reasoning that generalizes from partial examples. It’s an empirical and probabilistic judgment because it draws general conclusions from individual cases. For example, if you observe 100 crows and all 100 crows are black, you hypothesize that all crows are black. This is also known as content-extensive reasoning. The theory of science that deduces new observations and experimental results from these hypotheses and tests them against empirical data is called inductivist science. However, unlike deductive reasoning, the premises of inductive reasoning do not guarantee that the conclusion will always be true; they can only provide the best assumptions, because if a single non-black crow is found, the proposition that all crows are black will be false. Inductive reasoning is always fallible because it always presupposes a logical leap, which is inevitable in the case of inductive reasoning. As an alternative, logical positivists propose the hypothetic deductive methodology, which uses imagination, conjecture, or intuition to generate hypotheses instead of the thought process of generalizing from individual cases. The process of deductively deriving new observations and experimental results from hypotheses proposed through speculation or intuition, and then testing them again in light of experience, implies the traditional inductivist theory of science.
However, the hypothetic deductive methodology does not address the fundamental limitations of inductive reasoning. Through the principle of verifiability, logical positivists argued that only statements that can be verified through experience are meaningful propositions. This argument points to metaphysics and ethics as fields that are not subject to verifiability. They argue that these fields should be excluded from philosophy because they are not subject to verifiability. However, the problem is that even if inductivism and hypothetic deductive methodology are utilized, the fallacy that empirical universal statements cannot be verified eventually appears, and the theory of verifiability itself falls into the self-fulfilling prophecy that it is a metaphysical concept. Logical positivists accept this serious problem with the principle of verifiability and introduce the concept of ‘corroboration’ instead of ‘verification’. Unlike “proof” or “verification,” the degree of support for a hypothesis is expressed in terms of probability, and judgments are made about how likely it is that the hypothesis is true given the various pieces of evidence. However, there are still problems with this reductive proposal. The probability of a universal statement being corroborated by individual observations is, after all, the same as dividing a finite value by an infinite value, which means zero. In other words, no universal statement can be confirmed by empirical evidence.
Karl Popper argues that induction cannot solve the problem, and proposes an anti-proofist methodology to verify science using deduction alone. For example, the hypothesis “all crows are black” is proposed by the hypothetic deductive method, but if a non-black crow is found, it is a case of disproving the hypothesis because it does not fit the hypothesis. A logical positivist would say that if all the crows observed were black, then the hypothesis is proven. However, Popper would say that it has withstood attempts to disprove it. In other words, Popper says that every hypothesis must always presuppose that it could be wrong at some point. This is because even if a hypothesis has withstood attempts to disprove it so far, it can be immediately discarded at some point in the future if an instance of disproving it appears. In other words, Popper argues that “what is not disprovable is not science”.
Thus, disprovationalism overcomes the logical contradictions of inductive reasoning and offers a view of science that includes a cautious notion of progress. However, the idea that observational statements can be used to disprove universal statements faces another criticism. There is a serious problem with Popper’s disprovationalism, however, and it stems from the “theory dependence of observations. All observations have a theoretical component, and if there cannot be a theory-neutral language of observation, then the idea of testing theories through observation is undermined. According to Charmus, there is no such thing as an objective and certain observational statement.
It is impossible to be sure what is wrong, because a real hypothesis is not just a hypothesis, but a composite of many statements related to the hypothesis. Therefore, if a part of the whole is disproven, there is always the possibility that, because it is part of a whole, the theory as a whole can be saved by making the appropriate adjustments. This makes it impossible to make conclusive observations and tests that disprove a particular hypothesis, which means that Popper’s argument for discarding a hypothesis as soon as it is disproved becomes a logical problem.
Despite these limitations, disprovationalism clearly has advantages over inductivism. Because disproversialists emphasize the growth of science, their idea of corroboration is distinct in an important way. According to the inductivist position, a case of corroboration of a theory is determined solely by the logical relationship that exists between the observational statement that is corroborated and the theory that the observational statement supports. Only cases that inductively support a theory can be corroborating cases, and the more corroborating cases that can be found, the more support the theory has, and the more likely it is that the theory is true. But this non-historical, non-social, independent situation cannot exist at all. Science is based on existing theories and is heavily influenced by social backgrounds, philosophical positions, etc.
In conclusion, both the logical positivists’ inductivist theory of science and Karl Popper’s disprovationalist theory of science have their advantages and disadvantages, and no theory is perfect. Science is always changing, and this change is driven by constant criticism and verification. It’s through this process that science progresses, and it’s through this process that we gain better understanding and knowledge.
