John Wallis

Full Name: John Wallis
Nationality:

Profession: Mathematician and Cryptographer
Why Famous: Given partial credit for the development of infinitesimal calculus.

Introduced the symbol ∞ for infinity and similarly used 1/∞ for an infinitesimal.

Wallis also served as chief cryptographer for Parliament between 1643 and 1689 and later to the royal court.

Born: November 23, 1616
Birthplace: Ashford, England, United Kingdom
Star Sign: Sagittarius

Died: October 28, 1703 (aged 86)