## DA Diary

## Issac Newton

**Stutter, epilepsy**

Sir Isaac Newton , mathematician and physicist, is one of the foremost scientific intellects of all time. He entered Cambridge University in 1661; he was elected a Fellow of Trinity College in 1667, and Lucasian Professor of Mathematics in 1669. With two to three years of intense mental effort he prepared

*Philosophiae Naturalis Principia Mathematica*(

*Mathematical Principles of Natural Philosophy*) commonly known as the

*Principia.*

He was elected a Fellow of the Royal Society of London in 1671, and in 1703 he became President, being annually re-elected for the rest of his life. His major work,

*Opticks,*appeared the next year; he was knighted in Cambridge in 1705.

Newton was modest, diffident, and a man of simple tastes. He was angered by criticism or opposition, and harboured resentment; he was harsh towards enemies but generous to friends. In government, and at the Royal Society, he proved an able administrator. He has been regarded for almost 300 years as the founding examplar of modern physical science, his achievements in experimental investigation being as innovative as those in mathematical research.

In 1664, while still a student, Newton discovered measurable, mathematical patterns in the phenomenon of colour. He found white light to be a mixture of infinitely varied coloured rays. The roots of these unconventional ideas when first expressed in public in 1672 and 1675, provoked hostile criticism.

In mathematics he is famous for his solutions to the contemporary problems in analytical geometry of drawing tangents to curves (differentiation) and defining areas bounded by curves (integration).

According to the well-known story, it was on seeing an apple fall in his orchard at some time during 1665 or 1666 that Newton conceived that the same force governed the motion of the Moon and the apple. He calculated the force needed to hold the Moon in its orbit, as compared with the force pulling an object to the ground.