Augustus De Morgan
A 19th-century mathematical mind who formalized the logic of 'and', 'or', and 'not', creating laws that underpin modern computing.
1806–1871 (age 65)·British mathematician and logician·Birthday: June 27
Biography
Augustus De Morgan was a scholar of formidable range and a teacher of rare clarity, operating from his post at University College London. Irascible and principled—he once resigned on a point of academic freedom—he devoted his energy to making mathematics rigorous and accessible. His most enduring contribution was to formalize the symmetrical relationship between logical conjunction and disjunction, principles now known universally as De Morgan's laws. He also gave the process of mathematical induction its name and formal foundation. A prolific writer and critic, he corresponded with scientific luminaries of his day and penned hundreds of articles, fiercely debating the foundations of algebra and logic. His work created a bridge between classical logic and the emerging Boolean algebra, directly influencing the development of digital circuit design a century later.
#1 When Augustus Was Born
The biggest hits of 1806
Augustus's Life & Times
The world at every milestone
1806Born
1811Started school
1819Became a teenager
1822Could drive
1824Could vote
1827Turned 21
1836Turned 30
1846Turned 40
1856Turned 50
1866Turned 60
President: Andrew Johnson
1871Died at 65
President: Ulysses S. Grant
Key Achievements
- Formulated De Morgan's laws, fundamental rules of propositional logic and set theory.
- Formalized and named the principle of mathematical induction, a cornerstone of proof theory.
- Founded the London Mathematical Society and served as its first president.
- Wrote influential textbooks and a seminal book, Formal Logic, which advanced the study of symbolic reasoning.
Did You Know?
He was born in India, in the Madras Presidency (now Chennai).
He refused a fellowship at Cambridge University because it required a religious test.
He was an avid collector of puzzles, curiosities, and rare books.
The crater De Morgan on the Moon is named after him.
“The moving power of mathematical invention is not reasoning but imagination.”
