The Maintenance of Health

The modern Italian word for a notebook is taccuino. It comes from the medieval (and later) popularity of the Tacuinum Sanitatis. That name is a Latinized version of the Arabic Taqwīm aṣ‑Ṣiḥḥa ("Maintenance of Health"). It was written in the 11th century by Ibn Butlan of Baghdad, a physician and Christian theologian during the Abbasid Era.

The original was organized in synoptic tables: a way to present data in a simple and condensed manner, previously used for astrological tables. Ibn Butlan used them to present not just ways to treat illness and to maintain health, but also ways to prepare food and how and what to grow for health. Later manuscripts were lavishly illustrated, especially after the 14th century. (The illustration is of a facsimile edition made in 1986.)

Ibn Butlan set out the essential elements of health and well-being:

• sufficient food and drink in moderation
• fresh air
• alternations of activity and rest
• alternations of sleep and wakefulness
• secretions and excretions of humors
• the effects of states of mind

If one is not paying attention to these elements, illness occurs.

The Tacuinum includes lists of many vegetables, fruits, nuts, and herbs that are good for treating certain conditions. It also includes the dangers of excess consumption. As the manuscript was copied and distributed, changes were made, and not every copy includes every list. Some added remedies that were not in the original.

The word "humors" was italicized in Ibn Butlan's list because I wanted to draw attention to it. I've ignored discussing the medieval idea of humors for over a decade because I assumed people have already heard of them and I want this blog to focus on all the things that are not generally known. Of course, the details of humors are probably worth talking about. See you tomorrow.

The Lupin

When Pietro De Crescenzi wrote his ground-breaking (pun intended) work on soil management and agriculture, he showed a special interest in the lupin (that is the British English spelling; American English spells it lupine), a plant of the pea family. Although it wasn't until the 20th century that steps were taken to transform the lupin from a semi-domesticated crop to a modern crop plant, lupins have been cultivated for millennia. The seeds of one species have been found in an Egyptian tomb dating to the 22nd century BCE.

The lupin had a couple strikes against it. Although edible, it had a bitterness due to alkaloids; some varieties with less alkaloid content are called "sweet" lupins. Also, it had a bad reputation for "devouring" all the resources needed by other plants. The name comes from Latin lupinus, "of the wolf," the adjectival form of lupus, "wolf."

Despite this, Romans spread lupin use throughout the empire, soaking it in water before feeding it to humans or livestock. Failing to soak them in water long enough to leach out the alkaloids would lead to poisoning symptoms. (It is possible that our understanding of the name is less about devouring resources and more about what improperly prepared beans did to the consumer. Consider that the same Latin word for wolf also gives us the modern lupus to refer to a wasting disease. I cannot find a corroborating source for this theory, but it makes me wonder.)

On the other hand, the lupin was prescribed in Anglo-Saxon England for "devil-sickness." Lupins are high in manganese, and manganese deficiency is linked with recurring seizures. Is it possible that Northern Europe discovered the lupin as a treatment for epilepsy? This does not appear in any Mediterranean medical sources.

De Crescenzi saw value in the lupin as part of crop rotation:

Better still was the lupine. When raised for seed as one of the crops in a rotation, it was sown in October or November and harvested in June or July. When it was raised for fodder, it was cut somewhat earlier, but in either case it protected the land against winter rains. Several species were native to Italy, but Crescenzi made no distinction as to their use or method of cultivation. Some varieties of beans or vetch were occasionally substituted for lupine in rotations. [from Pietro De Crescenzi: The Founder of Modern Agronomy, Lois Olson, Agricultural History, Vol.18, No.1]

These days, the lupin/e (of which there are hundreds of varieties) is used for high-protein, high-fiber, and low-fat livestock feed, as well as for a nutritious flour substitute; and let's not forget its place in many gardens!

Its application as a treatment for epilepsy is an interesting twist, though, and makes me wonder how else the Middle Ages tried to explain and cure this particular ailment. Let's take a look at that next time.

Pietro De Crescenzi

Knowledge of proper agricultural techniques waned in the thousand years following the fall of Rome, except in monasteries, where texts on soil and crop management were preserved and studied. Into this setting, in the 13th century, came a Bolognese jurist named Pietro De Crescenzi.

De Crescenzi (c.1230 - c.1320) practiced as a layer from 1274 until 1300, during which time he traveled from city to city in the Lombard League. Traveling jurists were important, due to the concern that local lawyers would not be impartial. As he traveled, he took note of farming practices, comparing them to what he observed at the Dominican monastery in Bologna (his brother and several friends were members there, and its head was his confidant).

He retired at the age of 70 in c.1300 to his own farm in a suburb of Bologna. His application of efficient farming practices earned him such a reputation that King Charles II of Sicily asked him to write a treatise on the subject.

De Crescenzi produced the Liber ruralium commodorum ("Book of rural benefits") between 1304 and 1309, dedicated to Charles. It was so well received that Charles V of France ordered a French version in 1371. It was translated into Latin in 1471; 57 editions in different languages followed.

This was the first serious work on agronomy in a millennium, and borrowed heavily from the "lost" classical works on the subject. The structure is based on the De re rustica ("About rural things") of the 1st century Roman writer Columella, and De Crescenzi was clearly able to get a copy of the agricultural work of another Roman, Taurus Palladius, but he makes his own point in the introduction about soil that is fundamental to all farming:

The power of the soil should be investigated, and when it is discovered it is like an inestimable treasure that should be conserved with humility and patience.

He argued that a field giving poor yields should be left alone for four or five years until planted again. He recognized the need for crop rotation, "green manure" by plowing under what was growing wild, and regular fertilization—practices that make sense to us today, but that had fallen out of use for centuries.

The work is in 12 parts:

1. Siting and layout of a manor, villa or farm, considering climate, winds, and water supply; also the duties of the head of the estate
2. Botanical properties of plants and horticultural techniques
3. Agriculture of cereals and building of a granary
4. Vines and winemaking
5. Arboriculture—trees useful for food and medicine
6. Horticulture—plants useful for food and medicine
7. Management of meadows and woodland
8. Pleasure gardens
9. Animal husbandry and bee keeping
10. Hunting and fishing
11. General summary
12. Monthly calendar of tasks

You can see how extensive and thorough a guide for farming on a large and a household scale it is.

One of his emphases is on the utility of a particular plant, so I thought we'd talk next about its history and about what De Crescenzi has to say about it: the misnamed lupine.

Medieval Agronomy

It occurs to me that, in order to explain the importance of Pietro De Crescenzi, I should explain the thousand years that preceded him.

With the fall of Rome and barbarian invasions, farming started to suffer. That may be an unexpected statement, but there were reasons. With the loss of the Pax Romana ("Roman Peace"; formally, it refers to a 200-year span that ended in 180CE, but its influence lasted longer), invasions led many rural communities to migrate to cities for safety. Farmers who remained outside cities were focused on safety and managing their land with perhaps fewer farmhands. Marching armies devastated the arable land.

Roman irrigation systems were not maintained, both those that brought water to where it was needed and those that drained water from lowlands. Italy became increasingly swampy and a breeding ground for malaria, driving farming into smaller hilly areas where fields were overworked and erosion was more likely.

Classical Rome understood about erosion and soil management—Cato and Vergil had written about farming, and there was an expert named Taurus Palladius who wrote definitive Roman works on agronomy in the 5th century—but as civilization faltered, so did education and the knowledge of efficient agricultural practices. 

The Moorish lands maintained good practices, but Western Europe did not know about them, except in one area. Knowledge of the writings of Palladius and Mago the Carthaginian (whose 28 books written in Punic are lost, but we have Greek and Latin fragments) could be found in the enclaves that valued and collected and copied books: the monasteries. Monasteries in the Middle Ages maintained model farms, with the resources, knowledge, and manpower to get the most from the land without exploiting it.

In fact, it was the observation of farming techniques throughout Lombardy, and especially how monasteries managed their land differently, that got a jurist from Bologna thinking about agriculture. Although an expert in law with a reputation for fairness and legal knowledge, he started to take an interest in the differences he saw in farming techniques. When he retired to Bologna in his 70s, he decided to do something about what he had observed.

Tomorrow, we will see how this retired lawyer kick-started modern agronomy, the science of soil production and crop management.