Today in 1657 the Vatican placed Blaise Pascal’s Provincial Letters on the Index of Prohibited Books. The Index Librorum Prohibitorum ("List of Prohibited Books") was a list of publications deemed heretical or contrary to morality. The Letters defended Jansenism, which was an extreme version of St Augustine's theology which the Vatican had concluded was not very different from Calvinism. Pascals style of writing was very skilful and therefore the book was very popular.
Pascal was a French genius and multi-talented as a mathematician, physicist, inventor, philosopher, writer and Catholic theologian. He corresponded with Pierre de Fermat on probability theory, strongly influencing the development of modern economics and social science. In 1642, while still a teenager, he started some pioneering work on calculating machines establishing him as one of the first two inventors of the mechanical calculator. Like his contemporary Rene Descartes, Pascal was also a pioneer in the natural and applied sciences. When he was 23 years old he and his sister Jacqueline identified with the religious movement within Catholicism known as Jansenism. It was a particularly harsh form of theology, which began with the posthumously published work of the Dutch theologian Cornelius Jansen, Hugely influenced by St Augustine (Apr 24) it emphasized original sin, human depravity, the necessity of divine grace and predestination. and would be finally declared a heresy in the Catholic Church as being almost indistinguishable from Calvinism.
On the 23 of November, 1654, between 10:30 and 12:30 at night, Pascal had an intense religious experience and immediately wrote a brief note to himself which began: "Fire. God of Abraham, God of Isaac, God of Jacob, not of the philosophers and the scholars..." and concluded by quoting Psalm 119:16: "I will not forget thy word. Amen." He seems to have carefully sewn this document into his coat and always transferred it when he changed clothes; a servant discovered it only by chance after his death. This reinvigorated his belief and religious commitment and he began writing influential works on philosophy and theology. His two most famous works date from this period: the Provincial Letters and the Pensées, the latter contains the famous Pascal's Wager, known in the original as the Discourse on the Machine, If the Christian God does not exist, the agnostic loses little by believing in him and gains correspondingly little by not believing. If the Christian God does exist, the agnostic gains eternal life by believing in him and loses an infinite good by not believing.. In that year, he also wrote an important treatise on the arithmetical triangle. Between 1658 and 1659, he wrote on the cycloid and its use in calculating the volume of solids. However he wasn’t so successful with his theological defence of Jansenism as it was opposed by many in the Catholic hierarchy, especially the Jesuits.
Although the Jansenists identified themselves only as rigorous followers of Augustine of Hippo's teachings Jesuits coined the term Jansenism to identify them as having Calvinist affinities. Jansen had emphasized a particular reading of Augustine's idea of efficacious grace which stressed that only a certain portion of humanity was predestined to be saved. Jansen insisted that the love of God was fundamental, and that only perfect contrition, and not imperfect contrition (or attrition) could save a person. Jansen also insisted on justification by faith, although he did not contest the necessity of revering saints, of confession, and of frequent Communion. The heresy of Jansenism, as stated by subsequent Roman Catholic doctrine, lay in denying the role of free will in the acceptance and use of grace. Jansenism asserts that God's role in the infusion of grace cannot be resisted and does not require human assent. Catholic doctrine, in the Catechism of the Catholic Church, is that "God's free initiative demands man's free response"—that is, humans freely assent or refuse God's gift of grace.
Beginning in 1656–57, Pascal published his memorable attack on casuistry, a popular ethical method used by Catholic thinkers especially the Jesuits, and in particular Antonio Escobar. Pascal denounced casuistry as the use of complex reasoning to justify moral laxity and all sorts of sins. The 18-letter series was published between 1656 and 1657 and incensed Louis XIV. The king ordered that the book be shredded and burnt in 1660. Aside from their religious influence, the Provincial Letters were popular as a literary work. Pascal's use of humor, mockery, and vicious satire in his arguments made the letters ripe for public consumption, and influenced the prose of later French writers like Voltaire and Jean-Jacques Rousseau. Charles Perrault wrote of the Letters: "Everything is there—purity of language, nobility of thought, solidity in reasoning, finesse in raillery, and throughout an agreement not to be found anywhere else."
Pope Innocent X condemned five cardinal doctrines of Jansenism as heresy—especially the relationship between human free will and efficacious grace and the book would be later placed on the Index. The Index Librorum Prohibitorum ("List of Prohibited Books") was a list of publications deemed heretical or contrary to morality by the Sacred Congregation of the Index (a former Dicastery of the Roman Curia), and Catholics were forbidden to read them without permission. The index condemned religious and secular texts alike, grading works by the degree to which they were seen to be repugnant to the church. The aim of the list was to protect church members from reading theologically, culturally, or politically disruptive books. Such books included works by astronomers, such as Johannes Kepler's Epitome astronomiae Copernicanae which was on the Index from 1621 to 1835, works by philosophers, such as Immanuel Kant's Critique of Pure Reason, and editions and translations of the Bible that had not been approved. Editions of the Index also contained the rules of the Church relating to the reading, selling, and censorship of books. Some of the scientific theories contained in works in early editions of the Index have since long been taught at Catholic universities.
The Index of Prohibited Books of 1560 banned thousands of book titles and blacklisted publications, including the works of Europe's intellectual elites. The 20th and final edition of the index appeared in 1948, and the Index was formally abolished on 14 June 1966 by Pope Paul VI. The canon law of the Latin Church still recommends that works should be submitted to the judgment of the local ordinary (usually a bishop) if they concern sacred Scripture, theology, canon law, or church history, religion or morals. The local ordinary consults someone whom he considers competent to give a judgment and, if that person gives the nihil obstat ("nothing forbids"), the local ordinary grants the imprimatur ("let it be printed").
Pascale work outside of theology was very fruitful, particularly mathematics and his development of probability theory was his most influential contribution to mathematics. Originally applied to gambling, today it is extremely important in economics, especially in actuarial science. Pascal continued to influence mathematics throughout his life. The University of Waterloo, Ontario, Canada, holds an annual math contest named in Pascal's honour. He contributed to several fields in physics, most notably the fields of fluid mechanics and pressure. In honour of his scientific contributions, the name Pascal has been given to the SI unit of pressure and Pascal's law (an important principle of hydrostatics). His work in the fields of hydrodynamics and hydrostatics cantered on the principles of hydraulic fluids. His inventions include the hydraulic press (using hydraulic pressure to multiply force) and the syringe. A computer programming language is named for Pascal. And in 2014, the American producer of graphics processing units, known as GPUs, Nvidia announced its new Pascal microarchitecture, which is named for Pascal. The first graphics cards featuring Pascal were released in 2016.