Understanding the Boundaries of Scientific Knowledge
The Limits of Scientific Knowledge
The progress of science and technology are limited activities, both in their explanatory power and their ability to contribute to human progress. True scientific knowledge is characterized by being open (taking into account all possibilities), cautious (not claiming more than what is known), and critical.
Popper’s proper methodology emphasizes the inherently non-verifiable nature of scientific knowledge. He argued that a hypothesis can only be considered scientifically valid if it is falsifiable through rigorous testing. Scientific rigor should always lead to the search for contradictions, bringing us closer to truth. This method is governed more by the criterion of subsequent rebuttal rather than accumulated verification.
This criterion is known as the principle of falsifiability: a statement is scientific only if it can be potentially disproven by experience. Any position that denies such limitations risks falling into dogmatism or a reduction to mere facts. There is no possibility of knowing what lies beyond scientific experience. As Wittgenstein famously stated, “Whereof one cannot speak, thereof one must be silent.”
Science is a human endeavor, subject to social and psychological resistance from the scientific community and the prevailing attitudes of each era. Thomas Kuhn emphasized the sociological dimension of science: a new theory is not merely the result of new observations or tests. It is also a revolution or paradigm shift, which involves significant upheavals within the scientific community.
Popper and Kuhn have insisted that science is a historical construct. Imre Lakatos, building on their ideas, focused on the internal history of scientific research, particularly the development of theories. He proposed that laws and investigations are conducted under a research program.
Paul Feyerabend, on the other hand, suggested a form of methodological anarchism, encapsulated by the phrase “anything goes.” He argued that there is no single method to reach absolute scientific truth, and that scientific research must be free and responsible, though not always adhering to strict rules.
The ethics of responsibility in science emphasizes commitment to truth, and prioritizes social and environmental requirements.
Theory-Fact Relationship in Science
Three Key Hypotheses:
1. Reductionism: Theory Reflects Facts
This hypothesis posits that theory directly reflects facts as they are. Theories could be reduced to the facts themselves. This posture is very typical of positivism and inductivism.
2. Realism: Theories as Interpretive Frameworks
This view is more complex. Theories reflect reality but do not present it exactly as it is. As Popper stated, “theories are networks that allow us to capture realities.” The network itself is not the fish, but its structure (the size of its holes) determines what it can catch. Similarly, theories provide a framework to understand reality, but they are not reality itself. The relationship between theory and fact is not one of identity (like chicken soup being made of chicken), but rather one of representation or identification. For instance, a wardrobe number identifies a specific coat; the number is not the coat, but it allows us to locate and understand it.
3. Instrumentalism: Utility Over Truth
For instrumentalists, it does not matter whether a theory is true or false. What is important is its utility: whether it serves to explain things or to predict phenomena (as suggested by Kuhn).
Philosophical Perspectives on Scientific Progress
Positivism: Accumulation of Knowledge
Positivism asserts that science advances by the accumulation of theories and facts, implying continuous progress. It believes that progress arises from having more facts.
Objections to Positivism:
- There are no pure facts; all observation is theory-laden.
- Reductionism implies that scientific truth would never change, which contradicts historical evidence.
- Theories are considered true because they are proven by facts, but they are only provisional truths, as one cannot definitively prove a universal law.
Falsifiability: Popper’s Criterion for Science
Popper argued that scientific progress does not come from confirming theories, but from their refutation. To confirm a universal law, countless proofs might be needed, but only one refutation is sufficient to falsify it. Any statement that claims to be a scientific law must therefore be falsifiable.
Thomas Kuhn and the Nature of Paradigm Shifts
Kuhn contended that there are no pure facts; the only criterion that helps us decide which facts to consider and how to interpret them is the consensus of the scientific community. He explained the progress of science in two phases:
Phases of Scientific Progress:
1. Normal Science: Stability and Anomaly
This phase represents a period of clear progress, where a scientific community operates under a shared understanding of the world, including a set of beliefs about how the world is and the accepted methods. Through these beliefs, scientists observe facts, which can sometimes lead to the creation of anomalies. Persistent anomalies can lead to a scientific crisis, causing the beliefs of the scientific community to change, paving the way for a new paradigm.
2. Scientific Revolution: Paradigm Change
This phase involves the adoption of a new paradigm, encompassing new beliefs and new methods. A classic example is the shift from the geocentric (Aristotelian) to the heliocentric (Copernican/Pythagorean) model of the solar system. When scientists establish a new paradigm, the previous criteria for scientific understanding are often discarded. Paradigms are often considered incommensurable, meaning they cannot be directly compared or translated into one another.
Defining a Scientific Paradigm:
A paradigm is a set of philosophical ideas, scientific theories, and methodological rules that prevail within a scientific tradition”