Abiathar Crescas (, ) was a 15th-century

physician A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...

and astrologer from the

Crown of Aragon The Crown of Aragon ( , ) an, Corona d'Aragón ; ca, Corona d'Aragó, , , ; es, Corona de Aragón ; la, Corona Aragonum . was a composite monarchy ruled by one king, originated by the dynastic union of the Kingdom of Aragon and the County of ...

(now part of

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

). He was head astrologer to King John II of Aragon, father of King Ferdinand of Aragon. He could remove

cataracts A cataract is a cloudy area in the lens of the eye that leads to a decrease in vision. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colors, blurry or double vision, halos around light, trouble w ...

by a surgical procedure known as

couching In embroidery, couching and laid work are techniques in which yarn or other materials are laid across the surface of the ground fabric and fastened in place with small stitches of the same or a different yarn. The couching threads may be eithe ...

. 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.

References

* Philosophers of Judaism Medieval Jewish physicians of Spain Medieval Jewish astrologers 15th-century Aragonese Jews Medieval Jewish philosophers Spanish philosophers Year of birth unknown Year of death unknown Medieval Spanish astrologers {{Spain-med-bio-stub