When inspecting scientific knowledge, we should consider not only the knowledge itself but also the method by which that knowledge was acquired. Within scientific education, we frequently encounter teachings for which the experiment, observation, or other method used to obtain the knowledge is not mentioned or discussed. This can make it difficult to evaluate the evidentiary foundation upon which the knowledge rests.
For example, we may learn about the functional areas of the human brain without learning how scientists originally determined that different areas of the brain perform different functions. What observations or experiments were performed to obtain this knowledge? What evidence allowed scientists to associate particular functions with particular regions of the brain?
These questions are especially important when considering knowledge that was established before the development of modern technologies. The National Library of Medicine notes that the modern diagram of the functional areas of the human cerebral cortex was published in 1909 by German neuroanatomist Korbinian Brodmann. His work was based primarily on the anatomical organization of the cerebral cortex and the identification of different cortical areas through microscopic examination of brain tissue.
Knowledge about the functions of different regions of the human brain was also developed through observations of patients who had suffered brain injuries and subsequently displayed changes in their abilities or behavior. Such cases provided important evidence that damage to particular regions of the brain could be associated with impairments in particular functions.
Modern technology has since provided scientists with additional methods for investigating brain function. Functional magnetic resonance imaging (fMRI), for example, allows researchers to observe changes in brain activity associated with different tasks. However, fMRI was not introduced until much later, with modern fMRI research beginning in the early 1990s. Therefore, the knowledge we possess about the functional organization of the brain cannot simply be attributed to modern brain-imaging technology. Much of this knowledge was developed through earlier anatomical studies, observations of patients with brain injuries, and other forms of neurological research.
This raises an important question concerning the acquisition of scientific knowledge: What evidence was originally used to establish the teaching?
It is important, however, not to assume that an unknown experiment was necessarily unethical. The fact that a particular scientific teaching was established before modern technology does not demonstrate that unethical experimentation was used to obtain it. We must distinguish between what is documented and what is merely possible. If we do not know how a particular piece of knowledge was acquired, the rational response is to investigate its historical and evidentiary origins rather than assume an answer.
This distinction becomes particularly important when examining the history of medical experimentation. There are documented examples of unethical experimentation involving human beings. Psychosurgery, for example, involved surgical procedures performed on living patients and was practiced for decades during the twentieth century. Likewise, the Nazi medical experiments and the experiments conducted by Japan's Unit 731 constitute well-documented examples of unethical human experimentation.
These historical examples demonstrate why the method by which knowledge was acquired matters. If a scientific claim was established through unethical experimentation, that fact is relevant when evaluating the circumstances under which the knowledge was obtained. However, the existence of unethical experimentation in medical history does not by itself establish that a particular scientific teaching was obtained through such experimentation.
The same principle can be applied to questions concerning human survival. For example, what evidence was used to determine how long a human being can survive without food or water? Was this knowledge obtained through controlled experimentation, through observations of people experiencing famine or dehydration, through medical emergencies, through historical records, or through some combination of these sources? These questions are important because the answer tells us something about the evidentiary basis of the knowledge.
In some cases, the answer may be that no deliberate experiment was performed. Scientific knowledge is not acquired exclusively through experiments. It can also be acquired through observation, natural experiments, clinical cases, anatomical examination, historical records, and other systematic methods of investigation. Therefore, the question should not necessarily be, “What experiment was used?” but more broadly, “What method was used to obtain this information, and what evidence supports it?”
This is the broader principle I believe should be applied when inspecting scientific knowledge. Scientific teachings are often presented to students as established information without explaining how the information was originally acquired. Yet understanding the acquisition of knowledge is essential to understanding the knowledge itself.
When we encounter a scientific teaching, we should therefore ask: “How was this information obtained?” What experiment was performed? What was observed? What evidence was collected? What methods were used? And how did scientists move from that evidence to the conclusion being taught?
Questioning the acquisition of scientific knowledge does not mean rejecting scientific knowledge. Rather, it means examining its evidentiary foundation more carefully. By investigating not only what science teaches but also how the knowledge was obtained, we can develop a more precise understanding of the reliability, limitations, and evidentiary basis of scientific knowledge.
© 2026 Hazon, Nir
