Thomas Cajetan

Thomas de Vio Cajetan
Detail from Luther and Cardinal Gaetani by Francesco Salviati, c. 1550 – c. 1560
Born(1469-02-20)20 February 1469
Died9 August 1534(1534-08-09) (aged 65)
Education
Alma materUniversity of Padua
Philosophical work
EraMedieval philosophy
Region
SchoolThomism
Main interests
Notable worksSummula Caietani.
Bishop of Gaeta
ChurchCatholic Church
In office1519–1534
Other postCardinal-Priest of San Sisto
Orders
Ordination1491
Consecration1 May 1518
by Niccolò Fieschi
Created cardinal1 July 1517
by Pope Leo X

Thomas Cajetan OP (/ˈkædʒətən/ KAJ-ə-tən; 20 February 1469 – 9 August 1534), also known as Gaetanus or Cajetanus, commonly Tommaso de Vio or Thomas de Vio, was an Italian philosopher, theologian, the Master of the Order of Preachers 1508 to 1518, and cardinal from 1517 until his death. He was a leading theologian of his day who is now best known as the spokesman for Catholic opposition to the teachings of Martin Luther and the Protestant Reformation while he was the Pope's legate in Augsburg, and among Catholics for his extensive commentary on the Summa Theologiae of St. Thomas Aquinas.

He is not to be confused with his contemporary Saint Cajetan, the founder of the Theatines.