Leibniz is one of the first to work on the mathematical subject calculus. He was also a philosopher and physicist. Gottfried Wilhelm von Leibniz was born on July 1, 1646 in Leipzig, Saxony, which is now Germany. His father was Friedrich Leibniz, who was a professor of philosophy in Leipzig. His mother was Catharina Schmuck, who was the daughter of a lawyer. His father passed away when he was only six years old. Leibniz attended the Nicolai School in Leipzig when he was seven years old.

While in school, Leibniz was taught Aristotle’s logic, but he worked on improving the ideas. Leibniz studied his schoolwork, read his father’s books, including metaphysics books from both Catholic and Protestant authors. Leipzig was admitted to the University of Leipzig at the age of fourteen. He studied philosophy and mathematics, but mathematics was poorly taught. He received a bachelor’s degree in 1663 with the thesis De Principio Individui (On The Principle of The Individual). Leibniz learned important mathematical techniques from Erhard Weigel, who was Leibniz professor at Jena in the summer of 1663. Leibniz received a doctorate in law from the University of Altdorf in February 1667.

Although Leibniz main interest was science and mathematics, he also wanted to be an author. He memorized much of Aeneid by Virgil. Leibniz invented a calculator he took to Paris, France where he met with several prominent mathematicians. In 1672, he studied mathematics and physics under Christiaan Huygens (1629-1695). Huygens recommended he study Saint-Vincent’s work on summing series. Leibniz read it and made some discoveries on series of his own.

In January 1673 Leibniz went to England and demonstrated his calculating machine. After talking with Hooke, Boyle, and Pell, Pell found that some of Leibniz discoveries on series were in a book by Mouton. Because of this, Leibniz calculator was rejected. This disillusioned Leibniz. But later that year, after solving one of Jacques Ozanam’s (1640-1717) problems, he received more recommendations from Huygens that included works by Blaise Pascal (1623-1662), Honore Fabri (1607-1688), James Gregory (1638-1675), Gregorius Saint-Vincent (1584-1667), Rene Descartes (1596-1650), and Rene Francois Walter de Sluze (1622-1685).

Leibniz returned to Paris in August 1675. He and Tschirnhaus learned a lot while exchanging mathematical ideas. On November 21, 1675 Leibniz published a manuscript that used the integral notation and included the product rule for differentials. But soon he received a letter from the Englishman Isaac Newton (1643-1747). Newton complained that Leibniz had stolen his work on the calculus. Leibniz sent a letter back with his differential calculus, which was not included in Newton’s letter. They are credited as co-discoverers of calculus.

Leibniz notation was superior to any other notation being used during his lifetime, and his integral and derivative notation is still in use today. His contributions included differential calculus, the separation of variables, and a procedure for solving first order linear equations.

http://www-groups.dcs.st-and.ac.uk/~history/Biographies/Leibniz.html

http://scienceworld.wolfram.com/biography/Leibniz.html