The Royal Society of London planned an event to celebrate the tercentenary of Isaac Newton's birth in1942. However World War II made it essentially impossible and the celebrations did not take place untilJuly 1946. Lectures were given by E N da Costa Andrade, H W Turnbull, Niels Bohr and JacquesHadamard. John Maynard Keynes had also been invited to lecture but unfortunately he died in April1946, three months before the celebrations took place. Keynes was fascinated by Newton's manuscriptsand had been the first person to see some of the manuscript material by Newton which had been keptsecret until his papers were sold in 1936. Keynes' lecture, Newton, the man was delivered at thecelebrations by his brother Geoffrey Keynes. Here is the text of the lecture:-