Abiathar Crescas
Abiathar Crescas was a 15th-century physician and astrologer from the Crown of Aragon. He was head astrologer to King John II of Aragon, father of King Ferdinand of Aragon.
He could remove cataracts by a surgical procedure known as couching. In 1468 he restored the eyesight of King John in two simple operations, who was completely blind before the surgeries.
Crescas was a leader of Aragon's Jewish community.
