Macdonald Critchley in his amazing history of migraine (Critchley, 1966) reminds us that "Blaise Pascal was the victim periodically arisen in his frightening illusions. From time to time he chudilas huge cavern or abyss razverzshayasya on the left hand. In order to calm down, he sometimes shifted to this place any piece of furniture. On these periodic illusions told his contemporaries, such as l'Abbaye de Pascal. You can with some confidence to believe that this gulf was actually transient left-sided hemianopsia. "