Blaise Pascal was a mathematician, philosopher, and physicist in 17th century France. He made significant contributions to the mathematical and scientific world from a very young age before turning his attentions to religion and philosophy after a dramatic conversion at the age of 31. Pascal gave his name to several important mathematical and scientific concepts, and his religious works are considered masterpieces of the French language.
Blaise Pascal was born on 19 June 1623 in the town of Clermont in Auvergne, France. His mother died three years later, and the rest of the family relocated to Paris five years later. Blaise and his two sisters were very bright children, and their father, Etienne Pascal, encouraged them. Etienne was also an amateur mathematician and scientist, inspiring his son's early work in that vein. Blaise Pascal wrote a number of precocious mathematical treatises before the age of 18 and discovered what is now known as Pascal's theorem, regarding conical sections in projective geometry, at the age of 16.
When Blaise Pascal was 15 years old, the family moved to Rouen because his father's opposition to some of Cardinal Richelieu's policies made them unwelcome in Paris. Blaise Pascal continued his mathematical work, inventing a mechanical calculator later called the pascaline at the age of 18. Pascal's later mathematical work dealt with geometry and probability. In addition to his work in mathematics, Pascal contributed to the scientific fields of hydrodynamics and hydrostatics in his twenties. He invented the syringe and the hydraulic press and developed concepts that are now central to the field of hydrostatics.
Blaise Pascal suffered from a painful nervous condition since around the age of 18 and became partially paralyzed in 1647. Around the same time, his father was injured and attended by a physician who was also a Jansenist, one of the major Catholic factions in France at the time. Pascal began to think more about religion and to write about theological issues, but his life did not dramatically change until a harrowing experience in 1654. That year, Blaise Pascal nearly lost his life in a carriage accident, in which the horses ran off a bridge, leaving the carriage dangling over the edge. Pascal fainted and was unconscious for 15 days, at the end of which he had a mystical experience that inspired him to devote all of his attentions to religion.
Pascal's major religious works were the Provincial Letters and the Pensées, or "Thoughts." The Provincial Letters attacked what Pascal saw as corruption in the Catholic Church of his day. The Pensées, while unfinished, dealt with much broader questions of religious philosophy and has remained one of the most celebrated works of French literature.
Blaise Pascal became extremely ill at the age of 36 and died three years later. The exact cause of death was never determined, but an autopsy revealed several of his organs to be in very poor shape. Though Pascal's life was short, his contributions to both scientific and religious thought have had a lasting effect upon the world.
roser Post 2 
@robert13  As a mathematician, one of Pascal's greatest achievements was being one of the first people to consider probability as a mathematical concept. This basically changed the world by effecting the way people think about decisionmaking. Then there is Pascal's triangle which is a rather famous mathematical concept that I don't really understand well enough to be able to explain, perhaps someone else could? 


robert13 Post 1 
I'm mainly familiar with Pascal's religious works and philosophical writings. Besides inventing the mechanical calculator, what were some of Pascal's other contributions to mathematics? 