Many philosophers and medical scientists assume that disease categories or entities used to classify concrete cases of disease, are often defined by disease mechanisms or causal processes. Others suggest that diseases should always be defined in this manner. This paper discusses these standpoints critically and concludes that they are untenable, not only when 'disease mechanism' refers to an objective mechanism, but also when 'mechanism' refers to a pragmatically demarcated part of the total "objective" causal structure of diseases. As an alternative to principles that use the concept of disease mechanism or analogous concepts, a pragmatic approach is suggested and described. This approach has been suggested before, but in problematic or inadequate versions. This paper proposes a version compiled of two "pragmatic principles" and shows that they are much more adequate than the principle of disease mechanism. With reference to a case study of a still ongoing international discussion of various candidates for a classification system for malignant lymphomas, including REAL (Revised European-American Classification of Lymphoid Neoplasms) in which the concept of disease mechanism or analogous concepts plays a very small part, it is shown just how pivotal these two pragmatic principles can be in actual discussions of definitions of diseases. Finally, it is pointed out that with regard to modern philosophy of language it may, at least in some cases, be problematic to distinguish between the two pragmatic principles as they stand.
In the Danish Quality of Life Survey, we asked 10,000 people about their quality of life with the validated SEQOL questionnaire with more than 300 questions on their quality of life. How did they feel? How content were they with their lives? How happy were they? Did they feel their needs were fulfilled? And many more questions. We asked the questions we believed to be important for their quality of life (QOL). The results were quite surprising and forced us to recontemplate the following philosophical questions: What is quality of life, happiness, and meaning in life? What is a human being? Do we need a new biology? Is the brain the seat of consciousness? How do we seize the meaning of life and by doing so, will we become well again? What are the key concepts of quality of life? The meaning of life is connectedness and development. It is about realizing every opportunity and potential in one"s existence. The opportunities must be found and acknowledged. What do you find when you find yourself deep down? You find your real self and your purpose in life. You realize that you are already a part of a larger totality. Antonovsky called it "coherence". Maslow called it "transcendence". Frankl called it "meaning of life". We call it simply "being". To test if these philosophical questions are actually relevant for medicine, we looked at the consequences for patients being taught the quality of life philosophy. Quite surprisingly we learned from our pilot studies with "quality of life as medicine" that just by assimilating the basic concepts of the quality of life philosophy presented in this series of papers, patients felt better and saw their lives as more meaningful. The improvement of the patient"s personal philosophy of life seems to be the essence of holistic medicine, helping the patient to assume more responsibility for his or her own existence.