History of the nephron.

The many progressive achievements in knowledge about the structure and function of the nephron--the kidney's main morpho-functional unit--have always been influenced by philosophical theories, which for a long time have swung between vitalism and mechanism. From Galen's first imaginative vitalistic hypothesis, the scientific thought about the kidney's structure/function gradually moved to the iatro-mechanistic view promoted by Borelli, Bellini and Malpighi, to then meet Bowman's bright vitalistic-based theory. But Bowman's theory was rather soon replaced by novel yet still mechanistic theories proposed first by Ludwig and then Starling. Ludwig based his scientific approach to knowledge of renal function upon physics and chemistry; Starling eventually developed a "colloid-osmotic" theory.