Thinking about Sleep Across History
By Albert Kohn
In a certain sense, sleeping is the great unifying experience across time and place. Regardless of time period, almost every person spends one-third to one-half of their life asleep thus a good portion of our modern lives are identical to those of medieval people!
Yet, sleeping is not just the experience of unconsciousness. Recent scholarly work—particularly on the early modern period in Europe—has highlighted numerous differences in how people have structured their sleeping. While modern people have come to almost sacralize the ideal of one person per bed, the norm for most of history was to share beds; while we generally (attempt to) sleep continuously through the night, many in preindustrial Europe segmented their sleeping patterns so to be awake for a few hours in the middle of the night. These variations, though, pale in significance to the differences in how premodern people reflected upon their sleep.
For the entirety of the Middle Ages, bedtime brought with it fear for one’s physical and spiritual safety during the night. While we have limited medieval discussion of sleep itself, the common relationship with it is displayed in the rituals assigned to bedtime. Asides from prayers which sought God’s protection during the night, Christians would make the sign of the cross before falling asleep. James of Vitry (1160-1240) encourages this by warning that every child who dies during the night would have survived if only they had crossed themselves. A later work from the fifteenth century instructs lay people to confess their sins before going to bed because “to sleep in a state of sin is more dangerous than to sleep with a serpent.” The hegemony of protective bedtime rituals like these highlights how fear and the need for protection dominated the sleeping experience for much of the Middle Ages.
While this fear was tangled with medieval perceptions of the night, it was also the result of a lack of interest in the bodily process of sleeping. Outside of its role in dreaming, few medieval works considered the necessity and meaning of sleep. Those that did saw it primarily as an, at best, inconvenient result of postlapsarian existence in which one temporarily relinquished control over one’s mind and body. For these thinkers, sleep was a great abyss holding little real value. Such negativity prompted medieval preachers to eschew sleep and use it as a primary metaphor for impiety. In his theological dictionary, Alan of Lille defines writes that sleep represents “the death of Christ . . . the love of earthly things . . . [and] the torpor of laziness against doing good deeds.”
While the fear of sleep never dissipated, Aristotelian and Galenic texts, rediscovered in the thirteenth century, cultivated a new relationship with sleep. These writings become influential in medieval Latin society in the thirteenth century through Arabic translations acquired during the Christian reconquest of the Iberian Peninsula. In De Somno et Vigilia, Aristotle defines sleep as a necessary part of human life that can be shaped by our preparations for it. Galen, in his various medical texts, instructs that a healthy sleeping routine is an important part of each day.
These perspectives inspired new bedtime practices during the fourteenth and fifteenth centuries that saw sleep as important and potentially holy. Devotees were encouraged to meditate upon pious topics and read devotional works that would facilitate “good rest, good sleep and a good night in the name of God.” By utilising prayer to facilitate sleep rather than protect an individual during sleep these new practices appear in stark contrast to earlier rituals which virtually only addressed the dangers of sleep. One late medieval manuscript links these practices to the new teaching about sleep. Amongst its Galenic discussion of the importance of sleep to a life of piety, the work suggests some bedtime meditations and explains that “Aristotle said that the righteous have virtuous dreams and the wicked have wicked dreams because of their preceding thoughts.” By ritually preparing for bed and sleeping appropriately, this work imagines sleep as a pious act. This new relationship was a result of the Aristotelian and Galenic ideas that people brought to bed with them each night.
In comparison to our modern medicalized conception, both these frameworks for relating to sleep might seem foreign. Yet, while we might not pray or cleanse our minds of impious thoughts before bed, our vigilant use of meditation apps, journaling and calming bedtime teas would probably seem entirely reasonable to medieval people who had their own sleep hygiene. When we get into the context and details of these practices, though, the striking differences in thinking about sleep become abundantly clear.
 James of Vitry, ‘Sermo LXXIII, ad pueros et adolescentes’ in Analecta novissima spicilegii solesmensis, vol. 2, Joannes Baptista Pitra (ed.) (Paris, 1888), p. 439; ‘Sermon 73: For Children and Young People,’ John Shinners (trans.) in John Shinners (ed.), Medieval Popular Religion, 1000-1500, 2nd ed. (Peterborough, 2007), pp. 29-30
 “Ainsi l’on sera hors de danger Autrement dormir en estat de pechie est chose plus dangereuse que dormir auecung serpent.” Bodleian Library, MS Douce 365, 79r.
 Alan of Lille, Alani de Insulis Doctoris Universalis Opera Omnia, Jacques Paul Migne (ed.), col. 949.
 “Bon repos et bon dormir et bonne nuyt de par dieu ayons nous tous et toutes.” Bibliothèque nationale de France, Françaises, MS 927, 200r
 “Et a ce propoz dit Aristote que les vertueulz ont bons songes et les iniques soges iniques pour les pensees precedentes.” Bodliean Library, MS Douce 365, 79v.
Image: “Capitular letter illuminated with the scene of the Dream of the Magi”, Salzburg Missa, (Regensburg, c.1478-1489)Munich, Bavarian State Library, available via WikiCommons.