The result was DCLXVI, or six hundred sixty-six, or 666.
According to Stifel this proved that Pope Leo X was indeed the Antichrist. In
response to this, Peter Bungus, a Catholic theologian, decided to write a 700
page book to prove that it was not Leo X but Martin Luther who was the
Antichrist. Aside from these most interesting situations, Stifel did make some
real contributions to mathematics. His most famous work is the book Arithmetica
Integra. In this book is one of earliest logarithm tables, which is very similar
to the ones we use today. Stifel invented logarithms using a method unique to
the method that Napier used. Probably the most important contribution Stifel
made was in that he was the first European mathematician to use the addition,
subtraction, and square root symbols: +, -, and . Stifel also made other
contributions to algebra and basic arithmetic. Michael Stifel was, in the
kindest terms, an eccentric mathematician. His work as helped the development of
algebra, and he helped to shape modern mathematics. However his ideas on the end
of the world and about Leo X most likely overshadow the good he has done. A page
from Arithmetica ntegra Another page from Arithmetica Integra Roberval Gilles
Personne Roberval was born in Senlis, France, on August 10, 1602. He was a
French mathematician who died on October 27, 1675, in Paris. He came from a
family of simple farmers with a simple way of life. Since his family was poor,
Roberval had no official schooling. His family taught him until he left home
sometime before his fourteenth birthday. At the age of fourteen, Roberval's
interest in mathematics was born. Roberval traveled all over France earning
money by giving private lessons. He also talked with many professors at
universities about many advanced topics.
Once while Roberval was in Bordeaux, he
met Fermat. Because of this meeting, Roberval was selected to participate in the
group that met with Mersenne. Roberval arrived in Paris in 1628 where he met
with the group. He took a particular interest in Mydorge, Etienne Pascal, and
Blaise Pascal. It is interesting to note that even with the talent that was
present in this group, Roberval was the only one who went on to become a
professional mathematician. In 1632, Roberval was made professor of philosophy
at the College Gervais in Paris. Then in 1634, he was given the Ramus chair of
mathematics in the College Royale. This basically meant he was in head of the
math department at the college. One of Roberval's greatest accomplishments was
being elected to the Academie Royal des Sciences in 1666. He was one of the
founding members of the Academie. During his life, Roberval worked on many
topics. He was a supporter of the geometry of infinitesimals, which he said was
created by Archimedes. Roberval was unaware of the work that Cavalieri had done.
Roberval wrote a book about finding areas called Traite des Indivisibles. The
Academie published this with a collection of works. Roberval wrote treatises on
algebra and analytic geometry. He is known as the father of kinematic geometry
because of his work with the composition of movements. This is most useful in
finding tangents. Probably the most famous invention of Roberval's would be the
Roberval balance, which is used almost everywhere today. He also helped Italy
with the barometric experiments, and worked with Pascal on the vacuum apparatus
and experiments.
