Embryologic etiology is beginning to assume its rightful place in the study of medicine.
Where there is disproportion in development, a lack of balance, there is soil favorable to development of diseases. As Buchard stated: “It is the organism and not the microbe which makes the disease.” This thought was amplified by another noted French pathologist, Roger, when he wrote: “It is demonstrated today that anatomical alterations and clinical manifestations, in appearance identical, may develop under the dependence of different microbes; reciprocally the same microbe, according to conditions often difficult to determine, may determine maladies anatomically and chemically dissimilar.” All of which is to say that, before a morbid process can gain a foothold a certain aptitude must be present, and what this is determines the character of its expression.
And this aptitude is an attribute of the morphological state of the organism, and it has its origin in the phylogenetic and ontogenetic history of the individual. That is to say, what the organism has is the product of its heredity supplemented by that of its own creation during the process of growth and development; and what it has, as has been said, determines its functional capacities, its predispositions and susceptibilities.
This truth was clearly understood by Virchow when in 1877 he wrote:
“It is a fact, verified by experience, that those organs which in their development remain subnormal by defect of their mass offer a grave and more frequent inclination to disease; in other words, a predisposition which very often is interpreted as a simple weakness, but which in many cases is a real anatomical deficiency, visible and determinable in the tissue.” And then he continued, “I, at least, all consider i as contributing to the essentials of progress of the Science when we shall introduce the habit in the initiation of research concerning the cause of disease of single organs to consider as the first fundamental investigating their primitive constitution and putting in relation their affections with their structural quality”.
This expresses in terse yet comprehensive terms the view- point of the modern morphologist. What he strives for in every instance is a clear and full understanding of not only the character of the “primitive constitution” of single organs but of all the organs, being firmly convinced of the truth of the unity of action of the whole complex of organs, and next, puts “in relation” the totality of the symptom complex with the totality of the structural complex, remembering always that character of organization determines character of function; that predisposition, susceptibility and variation in function are attributes of particular conditions of structure, always immediately related to each other.
