“Little did I realize that from that day onwards I was never to be my old normal self again, that I had unwittingly and without preparation or even adequate knowledge of it roused to activity the most wonderful and stern power in man, that I had stepped unknowingly upon the key to the most guarded secret of the ancients, and that thenceforth for a long time I had to live suspended by a thread, swinging between life on the one hand and death on the other, between sanity and insanity, between light and darkness, between heaven and earth.”