Medical diagnosis is a science that involves more than the ability to recognize signs and symptoms and subsequently to group them into complexes or syndromes which in the light of past experience makes it possible to call a disease by name. Even a modest claim to proficiency requires a knowledge of the pathologic anatomy involved. But real genius in diagnosis is not achieved without the mental ability to portray also the functional disturbances concerned.
But all progress in eliciting obscure signs and new evidences of diseases and all discoveries in diversified fields of physiology have operated rather slowly in placing diagnosis on a physiologic basis. There are obvious reasons why the morphologic basis of disease antedated the functional conception. Morphologic pictures are concrete; they make a direct appeal to the senses. Physiologic processes are generally abstract; the mind can group them only through the employment of physical and chemical aids
WIGGERS CJ. PHYSIOLOGIC MEANING OF COMMON CLINICAL SIGNS AND SYMPTOMS IN CARDIOVASCULAR DISEASE. JAMA. 1931;96(8):603–610. doi:10.1001/jama.1931.02720340033008