Sir Isaac Newton - a beautiful mind revolutionising science

Newton was born in 1642 at Woolsthorpe Manor in Lincolnshire. Academic and rather unhappy, he enrolled at Trinity College, Cambridge, where his abilities were noticed by Isaac Barrow, Cambridge's first professor of mathematics. Barrow steered Newton away from the standard undergraduate texts and towards the big unsolved mathematical problems of the day, such as calculus - a way of describing how things change. Calculus would later be crucial for explaining the universe in mathematical terms. Newton also hunted out new works by men such as Descartes, who argued that the Universe was governed by mechanical laws.

Newton went on to write Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy). First published in 1687, this book established the principles of classical mechanics. Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for developing the infinitesimal calculus.

In Principia, Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint until it was superseded by the theory of relativity centuries later. Newton used his mathematical description of gravity to explain planetary motion, account for tides, the trajectories of comets, the precession of the equinoxes and other phenomena. It led to him finally eradicating the idea of the Earth being at the centre of the Solar System.

He demonstrated that the motion of objects on Earth and celestial bodies could be accounted for by the same principles. Newton's inference that the Earth is an oblate spheroid was later confirmed by the geodetic measurements of Maupertuis, La Condamine, and others, convincing most European scientists of the superiority of Newtonian mechanics over earlier systems.

Newton built the first practical reflecting telescope and developed a sophisticated theory of colour based on the observation that a prism separates white light into the rainbow of colours of the visible spectrum. His work on light was collected in his highly influential book Opticks, published in 1704.

Newton was a devout but unorthodox Christian. Beyond his work on the mathematical sciences, Newton dedicated much of his time to the study of alchemy and biblical chronology, but most of his work in those areas remained unpublished until long after his death in 1726.

The famous story of him seeing a falling apple at home in Woolsthorpe and 'discovering gravity' was recounted at a dinner party by Newton. The story was also told by other people who knew Newton, including his niece Catherine who cared for him in his later years. However, the myth that Newton was hit on the head by the apple was a later invention.

Further reading

• Isaac Newton: The man who discovered gravity - BBC
• Isaac Newton - Maths History
• Isaac Newton in London - Science Museum