Please Note: For brevity the term ‘disease’ is used here as a collective term for ‘disease’, ‘disorder’, ‘condition’ and ‘syndrome’, since all of these are defined by particular sets of signs and symptoms.
The concept of diseases in orthodox drug therapy is based on the assumption that the similarities between patients’ symptoms are more important than the differences:
Doctors have studied millions of sick people, and we must imagine that no two of these were ever completely identical as regards their clinical pictures and the underlying causal mechanisms, but in order to build up a medical science, it was essential to stress the similarities rather than the differences. 
Homeopathy, on the other hand, regards the actual clinical picture of each individual patient to be the essential starting point for a science of medicine. In considering the scientific validity of homeopathy as a medical system (or the validity of orthodox drug therapy, for that matter), it is important to ask whether the assumption that it is “essential to stress the similarities” is actually correct.
Orthodox drug therapy has used the concept of diseases for a long time, so it is useful to consider the following points:
Diseases are not synonymous with ill-health, since:Signs and symptoms may be present without a disease being identified;Signs and symptoms may be present in addition to an identified disease.
Diseases:Are officially recognised only when a definition is agreed;May be redefined in the future;May be defined by particular signs (e.g. acute kidney failure, fracture);May be defined by a range of signs and symptoms (e.g. measles);Are not expressed in identical symptoms in different people;May develop in different ways and at different rates in different people;Are diagnosed by the appearance of an agreed proportion of the range of signs and symptoms;May be diagnosed as the same in two people though they have symptoms which barely overlap;May be misdiagnosed;May be diagnosed without being present;May be undiagnosed when actually present (and sometimes fatally so).
Diseases are consequences not causes, and are products of:More than one causative factor;Unknown causative factors in some cases;Variable and often unknown influences on their progress.
There are three points of particular interest among those above:Diseases are the result of more than one primary factor;Disease symptoms are only a selection of all those actually present;Disease diagnosis involves a degree of uncertainty.
These points raise questions about the clarity and validity of the approach of orthodox drug therapy, and they create real difficulties when it comes to testing treatments.
Homeopaths start from the position that the body is a single organism, and that the totality of the signs and symptoms of the patient constitute the total response of that organism as an entity. Where the cause can be identified as a continuing external influence (such as poor diet or damp living conditions), removing this may be sufficient. in itself. Where there are correctable tissue abnormalities at birth, such as a hare-lip, surgical corrections should be made. Otherwise the symptoms are regarded as solely the body’s attempt to make itself well. This pattern of symptoms is then compared with the unique patterns of action of different substances on the human body in order to select a remedy. In homeopathy clarity is a primary requirement in the approach to treatment.
1. Henrik R Wulff, Stig Andur Pedersen & Raben Rosenberg, Philosophy of medicine an introduction (Oxford, Blackwell Scientific Publications, 1986), p.77.
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