Commentary for Bern Riddle 56: De sole


Date: Wed 31 Mar 2021
Matching Riddle: Bern Riddle 56: De sole

Remember how the last riddle was possibly about the sun, but maybe about a cloud instead. Well, although Riddle 56 is entitled “About the word” (De verbo) in several manuscripts, it is actually about the complex relationship between the sun and the moon. It seems that you can’t always trust scribes…

“Sun and moon at sunset, Tay Rail Bridge, Dundee. Photograph (by Ross2085) from Flickr (licence: CC-BY 2.0)”

We don’t think about the relationship between the sun and the moon very much today, but it was a topic of great interest for many of the most learned people in early medieval Europe. This was all because of one thing: the importance of the luni-solar calendar in calculating repeatable dates for Easter. This method of calendrical calculation became known as computus, from the Latin word computare (“to count or calculate”). Computus can be a very complex subject, but the fundamental rudiments are not too hard to understand—bear with me on this!

In the first few decades after the death of Christ, a tradition had developed in Rome, Jerusalem, and Alexandria where Easter would be celebrated on the Sunday after the Jews celebrated the Passover. In 325, at the First Council of Nicaea, the various churches decided to prohibit its celebration on the Passover and to calculate a date themselves. Everyone agreed that Easter should be on the first Sunday after the 14th day from the first new moon after the spring equinox. Unfortunately, they didn’t agree the nitty-gritty of the calculations, such as what date to calculate the equinox from, at what time each day should end and the next begin, and most importantly of all, what system should be used to integrate the lunar and solar calendars. This led to centuries of acrimonious disputes on the dating of Easter.

“An Easter table from the years 969-1006, from the B-section of the Leofric Missal, a computistical manual produced at Canterbury in the second half of the 10th century (Oxford, Bodleian Library, MS Bodley 579, folio 53r). The columns record the year, indiction (a rolling period of 15 years), epact (the age of the moon on 22nd March), concurrent (day of the week on 24th March), year in the 19-year cycle, date of the 1st new moon after the Spring equinox, and date of Easter. Photograph from Digital Bodleian (licence: BY-NC 4.0)”

Any method to date Easter had to be repeatable and predictable in advance. This meant integrating three elements in a perpetual calendar: the synodic lunar month (an average of approximately 29.5306 days) the tropical solar year (an average of approximately 365.2422 days), and the cycle of weekdays. The most challenging aspect of this was integrating the first two. 8, 30, 84, 95, and 112-year calendar cycles all achieved varying degrees of popularity at one time or another. However, the most accurate practical sequence was a 19-year cycle, and by the 9th century, this had become the dominant calendrical method in Western Europe.

Although the 19-year cycle was the most accurate way of integrating the lunar and solar calendars, it was not perfect, because the orbit of the moon around the earth and the earth around the sun have no direct link to one another. The calculation of the moon’s age on paper would often be several days out from the age of the moon in the real, observable world. Even after tinkering with some intercalations, the moon would still be 2.16 hours out of sync after 19 years. Many computists—including Bede—were very aware of this problem.

I hope that this all made sense. Now, we can get back to the riddle! It describes the sun and moon as brother and sister, who are also “husband” (maritus) and “wife” (coniunx). This incestuous relationship is further complicated by the fact that they are always apart from one another (line 3), and yet the sun manages to impregnate his sister (line 4) and then act as her midwife (lines 5-6). This is all rather bizarre and risqué, even for the Bern Riddles.

“ A diagram showing the days of the synodic lunar month. The tidal phases are marked around the perimeter, and a map of the world is at the centre. From the Thorney Computus, an early twelfth century English computus manual (Oxford, St. John's College, MS 17, folio 8r). Photograph from Digital Bodleian (licence: BY-NC 4.0)”

The genders of sun and moon are easy to explain—sol is a masculine noun and luna is feminine. In fact, Aldhelm, writing riddles in the seventh century, also calls them siblings. However, it is harder to explain why the relationship is a deviant one. Not only is it incestuous, but the idea of hiding children “behind a robe” suggests that they are covering this up. In an article that I wrote in 2020, I suggested that this was because the relationship between the sun and moon in computus was also rather complicated and problematic (Mogford, pages 232-3).

Since the sun and moon are said to always be apart in this riddle, the riddler is probably thinking of the time of the new moon—the only lunar phase when the moon is always nocturnal. In classical and medieval Latin literature, it was common to describe the full moon as metaphorically pregnant (nata). However, the riddler has cleverly extended this image to describe how the sun’s light illuminates the moon from a distance—and this gives us the curious idea of impregnation “from afar” (de longe).

But who are the “children” (nepotes) whom the moon births and the sun delivers? Minst argues that they are the night, whom the sun transforms into the day, but I don’t find this particularly convincing. I suspect that the riddler is thinking of the calendar here: the children are the months, who are born by the moon, but who are “covered together” (cunctos… textos) by the “single robe” (uno… peplo) of the solar year.

So, there we have it. Only in the wonderful Bern Riddles could the sun and moon become a brother and sister, who conduct an illicit relationship from a distance, with lots of babies! Next time you look up at the full moon shining in the night sky, remember the eccentric and slightly loony Bern Riddle 56!


References and Suggested Reading:

“Aenigma Tullii 56: De sole [Bern Riddle 54].” Translated by Karl J. Minst. In Fr. Glorie (ed.), Variae collectiones aenigmatum Merovingicae aetatis. Corpus Christianorum, Series Latina 133A. Turnhout: Brepols, 1968. Page 603.

Mogford, Neville. “The Moon and Stars in the Bern and Eusebius Riddles.” In Riddles at Work in the Early Medieval Tradition: Words, Ideas, Interactions. Edited by Megan Cavell and Jennifer Neville. Manchester: Manchester University Press, 2020. Pages 230-46.

Related Posts:
Bern Riddle 55: De sole
Bern Riddle 57: De sole