**
****René Descartes** - Philosopher, mathematician and physician of the XVIIth century. Author of the Discours de la méthode,
he said "I think, therefore I am".

**
****Augustin-Louis Cauchy** (1789-1857) - Cauchy's contributions to mathematics make him one of the most important mathematicians
of the nineteenth century. His work includes almost 800 papers covering vast areas of mathematics, but the singular contribution
which makes him one of my favorites was his work using a precise concept of the *limit* of a sequence. It's possible
Cauchy was the first to comprehend the implications of this concept's modern definition. (Briefly, that sequence *a*
has the limit *l* if, for any *epsilon* no matter how small, there is some *N* such that, for all *n*
greater than *N*, the *n*th term of *a* lies within *epsilon* of *l*.)

**
****Pierre-Simon, Marquis de Laplace** (1749-1827) - Some people believe Laplace should be remembered primarily for his *Méchanique
Céleste*, a five volume work on planetary motion. Others feel he should be remembered for his contributions to the theory
of probability. They may be right, but I think first of the linear transform which bears his name. The amazing properties
of the Laplace transform (and its inverse) can be used to solve some systems of linear differential equations by transforming
them into the Laplace domain, performing simple algebraic operations on them there, and then applying the inverse Laplace
transform to obtain the solution in the original domain.

**
****Blaise Pascal** (1623-1662) - Although he did not invent Pascal's Triangle it came to the attention of many Europeans
through Pascal's use of it in studies of combinatorics and probability, and thus it bears his name. His religious philosophy
is beyond the scope of this discussion, but his Wager argument is both clever and amusing enough to endear me to his thinking.

**
****Siméon-Denis Poisson** (1781-1840) - A pupil and friend of Laplace and Lagrange, he extended their work on celestial
mechanics. But his work in probability makes him one of my favorites. In the same paper he introduced both the Poisson distribution
and the law of large numbers.

_______________________________________________________________

__ANDREW HEATH__

- **Roger Godement**: algebraic topology

- **Elie Cartan**: algebraic topology, differential geometry

- **Marcel Berger**: differential geometry, riemannian geometry

- **Rene Thom**: chaos theory

- **Henri Cartan**: algebrac topology