Santiago Ramón y Cajal (Petilla de Aragón, May 1, 1852-Madrid, October 17, 1934) was a Spanish physician, specialized in histology and pathological anatomy. He shared the Nobel Prize for Medicine in 1906 with Camillo Golgi "in recognition of his work on the structure of the nervous system." Through his research into the mechanisms that govern the morphology and connective processes of nerve cells, he developed a new and revolutionary theory that began to be called the "neuron doctrine", based on the fact that the brain tissue is made up of individual cells. Humanist, as well as scientific, is considered the head of the so-called Generation of Sages.