Why Can't We Sleep? Understanding Our Sleeping and Sleepless Minds

If the time allotted to sleep was to become more and more fixed from the early nineteenth century, so was the very form of sleep itself. In an influential series of articles, and a book, At Day’s Close, the historian Roger Ekirch has argued that the basic form of human sleep prior to this period was biphasic. Rather than one single consolidated block, humans had a first and then a second sleep. Retiring around 9 or 10 p.m., they would sleep till midnight or 1 a.m., then rise for an hour or two – in a period known as ‘watching’, which meant less ‘looking’ than ‘being awake’ – before returning to their ‘second sleep’ till morning. Although the times for starting the first and second sleeps would shift historically and geographically, the biphasic pattern was more or less constant.