John Actuarius

Johannes Zacharias Actuarius (c. 1275 – c. 1328), son of Zacharias, was a Byzantine physician in Constantinople. He practiced with some degree of credit, as he was honored with the title of Actuarius, a dignity frequently conferred at that court upon physicians.

Very little is known of the events of his life, and his dates are debated, as some reckon him to have lived in the eleventh century, and others place him as recently as the beginning of the fourteenth. He probably lived towards the end of the thirteenth century, as one of his works is dedicated to his tutor, Joseph Racendytes, who lived in the reign of Andronikos II Palaiologos (1282–1328). One of his school-fellows is supposed to have been Apocauchus, whom he describes (though without naming him) as going upon an embassy to the north.

He wrote several books on medicinal subjects, particularly, an extensive treatise about the urines and uroscopy. Around 1299, he considered moving to Thessaloniki, but decided to stay in Constantinople; later, he was appointed chief physician to the Emperor.

Some of his works were translated into Latin, and published in the 16th century.

 This article incorporates text from a publication now in the public domain: Greenhill, William Alexander (1870). "Actuarius". In Smith, William. Dictionary of Greek and Roman Biography and Mythology. 1. pp. 17–18. 

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