Wallis, John (1616–1703)
John Wallis was the most influential English mathematician before Isaac Newton and an important contributor to the origins of calculus. He was a skilled linguist, was one of the first to proclaim in public William Harvey's discovery of the circulation of the blood, and had an extraordinary memory for figures. His Arithmetica Infinitorum was described as "the most stimulating mathematical work so far published in England" and introduced the original symbol for infinity (like an '8' lying on its side). It contained the germs of the differential calculus, and it suggested to Newton, who was delighted by it, the binomial theorem.
Together with Robert Boyle, Wallis formed a society where scientists congregated to discuss current scientific ideas. It led to the foundation of the Royal Society in 1660.