Giovanni (or Johannes) di Casali (or da Casale; c. 1320 – after 1374) was a

friar A friar is a member of one of the mendicant orders in the Catholic Church. There are also friars outside of the Catholic Church, such as within the Anglican Communion. The term, first used in the 12th or 13th century, distinguishes the mendi ...

in the

Franciscan The Franciscans are a group of related organizations in the Catholic Church, founded or inspired by the Italian saint Francis of Assisi. They include three independent Religious institute, religious orders for men (the Order of Friars Minor bei ...

Order, a

natural philosopher Natural philosophy or philosophy of nature (from Latin ''philosophia naturalis'') is the philosophical study of physics, that is, nature and the physical universe, while ignoring any supernatural influence. It was dominant before the developme ...

and a

theologian Theology is the study of religious belief from a religious perspective, with a focus on the nature of divinity. It is taught as an academic discipline, typically in universities and seminaries. It occupies itself with the unique content of ...

, author of works on theology and science, and a

papal legate 300px, A woodcut showing Henry II of England greeting the Pope's legate. A papal legate or apostolic legate (from the ancient Roman title '' legatus'') is a personal representative of the Pope to foreign nations, to some other part of the Catho ...

. He was born in

Casale Monferrato Casale Monferrato () is a town in the Piedmont region of Northwest Italy, northwestern Italy, in the province of Alessandria. It is situated about east of Turin on the right bank of the Po River, Po, where the river runs at the foot of the Montfe ...

around 1320‘Giovanni da Casale’
''Enciclopedie on line'', Treccani. and entered the

Franciscan order The Franciscans are a group of related organizations in the Catholic Church, founded or inspired by the Italian saint Francis of Assisi. They include three independent Religious institute, religious orders for men (the Order of Friars Minor bei ...

in the Genoese province. He was lecturer in the Franciscan stadium at

Assisi Assisi (, also ; ; from ; Central Italian: ''Ascesi'') is a town and comune of Italy in the Province of Perugia in the Umbria region, on the western flank of Monte Subasio. It is generally regarded as the birthplace of the Latin poet Prope ...

from 1335 to 1340. He subsequently was lector at

Cambridge Cambridge ( ) is a List of cities in the United Kingdom, city and non-metropolitan district in the county of Cambridgeshire, England. It is the county town of Cambridgeshire and is located on the River Cam, north of London. As of the 2021 Unit ...

ca. 1340 to 1341, where he encountered the mathematical physics developed by the

Oxford Calculators The Oxford Calculators were a group of 14th-century thinkers, almost all associated with Merton College, Oxford; for this reason they were dubbed "The Merton School". Their work incorporated a logical and mathematical approach to philosophical p ...

. He was also an

inquisitor An inquisitor was an official (usually with judicial or investigative functions) in an inquisition – an organization or program intended to eliminate heresy and other things contrary to the doctrine or teachings of the Catholic faith. Literall ...

Florence Florence ( ; ) is the capital city of the Italy, Italian region of Tuscany. It is also the most populated city in Tuscany, with 362,353 inhabitants, and 989,460 in Metropolitan City of Florence, its metropolitan province as of 2025. Florence ...

, and a lector in

Bologna Bologna ( , , ; ; ) is the capital and largest city of the Emilia-Romagna region in northern Italy. It is the List of cities in Italy, seventh most populous city in Italy, with about 400,000 inhabitants and 150 different nationalities. Its M ...

from 1346 to ca. 1352. In 1375 Pope

Gregory XI Pope Gregory XI (; born Pierre Roger de Beaufort; c. 1329 – 27 March 1378) was head of the Catholic Church from 30 December 1370 to his death, in March 1378. He was the seventh and last Avignon pope and the most recent French pope. In 1377, ...

appointed him papal legate to the court of King Frederick of Sicily.Maarten van der Heijden and Bert Roest
‘Franaut-J’
, ''Franciscan Authors, 13th – 18th Century: A Catalogue in Progress''. About 1346 he wrote a treatise ''De velocitate motus alterationis'' (On the Velocity of the Motion of Alteration) which was subsequently printed in

Venice Venice ( ; ; , formerly ) is a city in northeastern Italy and the capital of the Veneto Regions of Italy, region. It is built on a group of 118 islands that are separated by expanses of open water and by canals; portions of the city are li ...

in 1505. In it he presented a graphical analysis of the motion of accelerated bodies. His teachings in

mathematical physics Mathematical physics is the development of mathematics, mathematical methods for application to problems in physics. The ''Journal of Mathematical Physics'' defines the field as "the application of mathematics to problems in physics and the de ...

influenced scholars at the

University of Padua The University of Padua (, UNIPD) is an Italian public research university in Padua, Italy. It was founded in 1222 by a group of students and teachers from the University of Bologna, who previously settled in Vicenza; thus, it is the second-oldest ...

and, it is believed, may have ultimately influenced the similar ideas presented over two centuries later by

Galileo Galilei Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642), commonly referred to as Galileo Galilei ( , , ) or mononymously as Galileo, was an Italian astronomer, physicist and engineer, sometimes described as a poly ...

.Marshall Clagett, ''The Science of Mechanics in the Middle Ages,'' (Madison: Univ. of Wisconsin Pr., 1959), pp. 332-3, 382-391, 644

References

{{DEFAULTSORT:Casali, Giovanni di 1370s deaths 14th-century Italian Roman Catholic priests Italian Franciscans Catholic clergy scientists 14th-century Italian Roman Catholic theologians 14th-century Italian mathematicians Year of birth unknown Medieval physicists Year of birth uncertain 14th-century writers in Latin

See also

References