Arnold Joseph Toynbee (April 14, 1889 – October 22, 1975) was an English historian, a philosopher of history, an author of numerous books and a research professor of international history at the London School of Economics and King’s College London. Wikipedia

“Toynbee has recorded how he once experienced a sudden flash of the whole of history, ‘all that had been, and was, and was to come.’ And Arthur Koestler has described how, sentenced to death in a Spanish jail, he tried to work out Euclid’s proof that there is no prime number, and, as he succeeded, was swept into a kind of mystical ecstasy, a sense of floating on his back ‘in a river of peace, under bridges of silence,’ at the thought that man has succeeded in saying something concrete about the infinite. Troubled by some faint sense of annoyance at the back of his mind, he remembered suddenly that he was due to be shot the next day, then brushed it aside with the thought, ‘So what? Have you nothing more serious to worry about/'”

–Colin Wilson in The Misfits: A Study of Sexual Outsiders”

Arthur Koestler (September 5, 1905 – March 1, 1983) was a Hungarian-born author and journalist. Koestler was born in Budapest, and apart from his early school years, was educated in Austria. In 1931, Koestler joined the Communist Party of Germany, but he resigned in 1938 after becoming disillusioned with Stalinism. Wikipedia