On September 24, 1501, Italian Renaissance mathematician, physician, astrologer and gambler Gerolamo Cardano was born. He wrote more than 200 works on medicine, mathematics, physics, philosophy, religion, and music. But, he is best known for his gambling that led him to formulate elementary rules in probability, making him one of the founders of probability theory.
On August 21, 1789, French mathematician Augustin-Louis Cauchy was born. He is considered one of the greatest mathematicians during the nineteenth century. There are 16 concepts and theorems named for Cauchy, more than for any other mathematician. Cauchy was one of the most prolific mathematicians of all times. Cauchy wrote 789 papers, a quantity exceeded only by Euler and Cayley, which brought precision and rigor to mathematics.
On August 11, 1464, German philosopher, theologian, jurist, and astronomer Nikolaus of Cusa (in latin: Nicolaus Cusanus) passed away. He is considered as one of the first German proponents of Renaissance humanism. His best known work is entiteled 'De Docta Ignorantia' (Of the Learned Ignorance), where also most of his mathematical ideas were developed, as e.g. the trial of squaring the circle or calculating the circumference of a circle from its radius.
On August 4, 1805, Irish physicist, astronomer, and mathematician William Rowan Hamilton was born. He made important contributions to classical mechanics, optics, and algebra, but is perhaps best known as the inventor of quaternions, a number system that extends the complex numbers.
On July 13, 1527, Welsh mathematician, astronomer, astrologer, occultist, navigator, imperialist and consultant to Queen Elizabeth I, John Dee was born. He is considered one of the most learned men of his age. Besides being an ardent promoter of mathematics and a respected astronomer, in his later years he immersed himself in the worlds of magic, astrology and Hermetic philosophy. One of his aims was attempting to commune with angels in order to learn the universal language of creation.