Youssef Ziedan is an Egyptian writer and scholar who specializes in Arabic and Islamic studies. He is a public lecturer, columnist, and prolific author of more than 50 books. He is also director of the Manuscript Center and Museum at the Bibliotheca Alexandrina.

ʿAlāʾ al-Dīn Abū al-Ḥasan ʿAlī ibn Abī Ḥazm al-Qarashī, known as Ibn al-Nafīs, was an Arab polymath whose areas of work included medicine, surgery, physiology, anatomy, biology, Islamic studies, jurisprudence, and philosophy. He is known for being the first to describe the pulmonary circulation of the blood. The work of Ibn al-Nafis regarding the right sided (pulmonary) circulation pre-dates the later work (1628) of William Harvey's De motu cordis. Both theories attempt to explain circulation. 2nd century Greek physician Galen's theory about the physiology of the circulatory system remained unchallenged until the works of Ibn al-Nafis, for which he has been described as "the father of circulatory physiology".