Medical Epistemology

Medical ethics and bioethics in medicine have marginalized the philosophy of medicine. The philosophy of medical knowing and knowledge, i.e., medical epistemology, seems to be something particularly unknown in medicine. It will challenge the community of medical philosophers in the years to come. In this Part III of the book, one will find a foundational study of medical epistemology that starts with the explication of the traditional concept of knowledge ("knowledge is justified true belief") to show that it is problematic and cannot be relied on in medicine.

Knowledge is a subjective state of the knower like her hopes and beliefs. But it may be artificially detached from the knower by means of transforming it into intersubjectively available sentences. In this way it becomes amenable to scientific and metascientific, epistemological analyses.

The syntax of medical knowledge is examined and a distinction is made between problematic sentences, first-order sentences, modal sentences, probabilistic sentences, and fuzzy sentences to show that, for the most part, medical knowledge is represented by fuzzy sentences. The impact of the syntax of medical knowledge on its semantics is demonstrated by analyzing the logical structure of medical hypotheses and their possible truth values. It is pointed out that the term “theory” plays an important role in medicine. To inquire into the nature of medical theories and their epistemology, the concept of theory is extensively discussed by presenting (i) the traditional view that has come to be termed the “statement view”; (ii) the so-called semantic view; and (iii) a recent view in the general philosophy of science referred to as the “non-statement view” of theories, or “structuralism” (not to be confused with the Swiss and French structuralism in linguistics and the humanities, or with structuralism in mathematics). The latter view is a well-elaborated metatheory and is briefly introduced. In light of this metatheory, some elementary steps are taken in the direction of a structuralistic analysis of medical theories.

Several types of medical knowledge are distinguished: classificatory, causal, experimental, theoretical, practical, and clinical knowledge. This differentiation will be of assistance later on when inquiring into the nature of medicine.

To explore the semantics of medical knowledge, we resort to the classical concept of knowledge mentioned above. It is shown why this concept is inadequate for use in medicine and medical epistemology. Also the main theories of truth and justification, including theories of confirmation, likelihood tests and significance tests, are discussed to demonstrate that medical knowledge is not knowledge in the classical sense. Large parts of it are not verifiable, and there is as yet no satisfactory concept of empirical justification to characterize medical knowledge as empirically justified. Other concepts of knowledge are needed that do justice to what is called knowledge in medicine. The question is analyzed whether medical knowledge and concepts refer to some human-independent realities, or whether they are human constructs, and as such, socially conditioned. Cogent arguments are given against realism and in support of the latter alternative based on social and communitarian epistemology. Medical knowledge turns out a social construct created by testimonial processes in medical communities, with the individual knowledge of a knower being a social status lent by an epistemic community. For this reason, social constructivism may provide a viable tool for the analysis of epistemological issues in medicine.

The final chapter of this part offers a novel theory of experimental-scientific knowledge referred to as technoconstructivism. Scientific experiments in general and medical experiments in particular are reconstructed as production systems to show that they are models for the concept of the input-output machine introduced earlier in the book. As such, they may be categorized as machines. Since the main output of these machines is usually referred to as knowledge, they are called epistemic machines. Experimental-medical laboratories house such knowledge-producing epistemic machines. They may therefore be viewed as epistemic factories. Today an epistemic factory is networked with the Global Knowledge-Making Engine (GKME) that consists of the Internet, intranets, and local area nets. Driven by artificial intelligence, the GKME is on the verge of automating the production of knowledge in epistemic factories. Experimental-scientific research is thus becoming industrialized with its product being knowledge. In a not-too-distant future, then, it will be pointless to ask whether such an industrial product does or does not possess epistemological properties such as truth, falsehood, truthlikeness, probability, justifiedness, credibility, reliability, plausibility, etc. The product will simply be handled as a modularized, portable and copyable commodity, and applied according to its expected utility.

This completes Part III consisting of 4 chapters and 173 pages.