Pathology is no longer the" dead science" it was reputed to be a few decades ago. The famous Canadian pathologist, William Boyd, expressed the newer attitude aptly when he stated that pathology should no longer be concerned simply with describing the" WHAT" of disease, but must be increasingly con­ cerned with the "HOW" and the "WHY". By this he implied that the preoccupa­ tion of the usual student of disease in the architecture of diseased tissues and descriptions of participating cells, their staining characteristics, etc. , must give way to study and understanding of the dynamics of each disease process, the pathogenetic mechanisms producing the changes in body tissues. This study is not limited simply to etiologic factors and portals of entry to the site of the lesion, but includes the physical and chemical factors involved, the variations of host response conditioned by immunologic reactions of differing intensities, enzymatic excesses or deficiencies, and a host of other variables of little known character such as the prostaglandins which definitely affect the disease process. No longer is the pathologist one who looks at sections of diseased tissue merely for differentiation of disease, but truly a pathologist studies disease.

Pathology is no longer the" dead science" it was reputed to be a few decades ago. The famous Canadian pathologist, William Boyd, expressed the newer attitude aptly when he stated that pathology should no longer be concerned simply with describing the" WHAT" of disease, but must be increasingly con­ cerned with the "HOW" and the "WHY". By this he implied that the preoccupa­ tion of the usual student of disease in the architecture of diseased tissues and descriptions of participating cells, their staining characteristics, etc. , must give way to study and understanding of the dynamics of each disease process, the pathogenetic mechanisms producing the changes in body tissues. This study is not limited simply to etiologic factors and portals of entry to the site of the lesion, but includes the physical and chemical factors involved, the variations of host response conditioned by immunologic reactions of differing intensities, enzymatic excesses or deficiencies, and a host of other variables of little known character such as the prostaglandins which definitely affect the disease process. No longer is the pathologist one who looks at sections of diseased tissue merely for differentiation of disease, but truly a pathologist studies disease.