[Disease as a biological event]

The paper discusses the general concept of disease on which modern medicine is founded. Following a brief historical review of the various ideas which have been put forward over the centuries, the paper focuses on the concept of "homeostasis" and the "body's adaptation to the environment", demonstrating that the latter is an absolutely fundamental aspect for the continuation and transmission of life. The Authors sustain that our current use of the term "disease" is both vague and ambiguous, and that the concept of disease cannot be separated from that of hoemostasis and adaptation to the environment. In conclusion, disease represents an alteration of the living body's homeostatic mechanisms which impede normal physiological functions and make the body less able or incapable to adapt to environmental changes, thus leading to morphological, biochemical and physiological damage. In line with Konrad Lorenz's affirmations, it is clear that "pairs of concepts like 'healthy and ill', 'normal and pathological', can only be defined on the basis of a greater or lesser possibility of survival which every individual quality offers a living organism within a given environment". In addition, whereas physiological phenomena are characterised by a clear end (telos), pathological phenomena are closely linked to the difficulty of attaining this end. Other theses regarding the concept of disease are discussed in the second half of the paper: a) that disease represents a morphological alteration at a tissue or cellular level; b) that disease may be identified as subjective suffering; c) that disease is a purely physiological and chemical event; d) that disease is a bio-psychosocial phenomenon. The problems concerning all these hypotheses are analysed and it is underlined that disease above all represents a biological event marked by functional changes, which interrupts the coordination of vital activities and impedes the conservation of life.