# Henri Poincaré (1854-1912)

Born in 1854 in Nancy, France, Henri Poincaré was a visionary mathematician and philosopher whose innovative ideas continue to be used daily by engineers and scientists today.

After initial studies in mathematics and engineering, Poincaré was appointed as Professor of Mathematics at the University of Paris in 1881 and soon became well known for his ground-breaking research. His theoretical work focused on resolving problems such as number theory, differential equations (used to calculate how variables change in a dynamic system) and algebraic topology (equations which describe shapes and spaces). He also considered many topics in applied science such as celestial mechanics, fluid dynamics, optics, electricity and telegraphy. In particular, his work on celestial mechanics laid the foundations for Einstein’s subsequent theory of special relativity, while his mathematical work on dynamics led to the development of chaos theory.

As a result of his intense mathematical research, Poincaré became interested in philosophy and psychology, particularly in relation to human thought processes and problem-solving. He was also keen to share his passion for science and mathematics with general audiences and wrote a number of popular science books such as The Value of Science (1905) and Science and Method (1908).

Poincaré received numerous awards and honours throughout his life, both from national and international organisations. An asteroid and a crater on the Moon are both named in recognition of his research.

He died in Paris in 1912.