Out of several, the most famous of these conferences took place in October 1927. Called The Fifth Solvay International Conference on Electrons and Photons, where the world’s most notable physicists met to discuss the newly formulated quantum theory. The leading figures were Albert Einstein and Niels Bohr. Einstein, disenchanted with Heisenberg’s uncertainty principle, remarked “God does not play dice”. Bohr replied, “Einstein, stop telling God what to do”. (See Bohr–Einstein debates.) 17 of the 29 attendees were or became Nobel Prize winners, including Marie Curie, who alone among them, had won Nobel Prizes in two separate scientific disciplines.