A system of grace developed by Cornelius Jansen, or Cornelius Jansenius (1585-1638), theologian at Louvain and later Bishop of Ypres. As a school of theology, it should be seen in two stages, namely the original position of Jansenius and its later development by his followers.
Jansenius' own teaching is contained in the book Augustinus, which he spent years in writing and was published two years after his death. According to Jansenius, man's free will is incapable of any moral goodness. All man's actions proceed either from earthly desires, which stem from concupiscence, or from heavenly desires, which are produced by grace. Each exercises an urgent influence on the human will, which in consequence of its lack of freedom always follows the pressure of the stronger desire. Implicit in Jansenism is the denial of the supernatural order, the possibility of either rejection or acceptance of grace. Accordingly those who receive the grace will be saved; they are the predestined. All others will be lost. Jansenism was condemned as heretical in five major propositions by Pope Innocent X in 1653. It was recondemned by Pope Alexander VII in 1656, when Jansenists claimed that their doctrine was misrepresented.
The later developments of Jansenism were built on the earlier foundations but went beyond them in a number of ways. Stress on God's selective salvation produced a general harshness and moral rigorism, denying God's mercy to all mankind. Disregard of papal teaching led to an arbitrary attitude toward the use of the sacraments, notably reducing the frequency of penance and the Eucharist, and giving rise to Gallicanism, which denied papal primacy and infallibility. In 1794, Pope Pius VI condemned a series of eighty-five propositions of the Italian Jansenists led by Scipione de' Ricci, Bishop of Pistoia and Prato. Among the propositions was the claim that the authority of the Church depends on the consent of its members and that the jurisdiction of a diocesan bishop is independent of the Pope.