Claudius Galenus or Galen of Pergamon was referred to as the “Father of Experimental Physiology”. A prominent Greek physician, surgeon & philosopher in the Roman Empire, Galen was ranked second behind Hippocrates in the knowledge of medicine. He influenced the development of various scientific disciplines, including anatomy, physiology, pathology, pharmacology, and neurology, as well as philosophy and logic. Galen was set apart from his rival when he begin to diagnose soldiers returning from battle with smallpox & measles, and recorded their symptoms and prognoses.
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