Transcript coming soon

Last time, I talked about a story reported by Herodotus, about the Egyptian Pharaoh Psamtik I, who allegedly attempted to investigate whether the Egyptians or the Phrygians were the oldest nation on earth, by having two babies raised for the first two years of their lives without exposure to language, to determine what language they would default to. After two years, they apparently said the word bekos, the Phrygian word for bread, leading the Pharaoh to the bizarre conclusion that the Phrygians of Central Anatolia surpassed even the extraordinary antiquity of ancient Egyptian civilisation.

Now, from Memphis, we travel Northwest, along the western branches of the Nile delta, over the city of Alexandria, and out into Aboukir Bay and the shining blue Mediterranean. Passing the western end of Crete, and the rough hills of the Ionian Islands, we make landfall, 1800 years later, in Puglia, on the flat plain east of the Appenines. Passing a chequered landscape of vineyards and olive groves, we eventually reach the city of Foggia, home of the King of Sicily, Frederick II.

After the Western Roman Empire Collapsed, Sicily changed hands several times between Ostrogoths, Vandals, and the Eastern Roman Empire, until the 9th century, when the Aghlabid Emirate, vassals of the great Abbasid Caliphate, would gradually conquer the island. The Muslim Aghlabids would remain in control of Sicily, and sometimes parts of the Italian Mainland, until 1061, when the Norman adventurer Robert Guiscard arrived and took 30 years to conquer the entire island from the Aghlabids. In 1130, Roger II, the third count of Sicily and nephew of Robert Guiscard, was crowned King of Sicily.

Roger II's Sicily is known for an unusual hybrid culture that developed there, typical of its position right at the centre of the Mediterranean, at the meeting point between the Eastern and Western Mediterranean, merging elements from the cultures of the three civilisations that had ruled the island - the Greeks, the Muslim Arabs, and the Latin Christian Normans. Roger II, although a Latin Christian himself, appointed Arabs and Greeks to important administrative roles in his court, and patronised Arab and Greek artisans, producing architecture with influences from all three of the civilisations that collided in his Kingdom. Take as an example the Capella Palatina, in Roger's capital, Palermo, which broadly takes the form of a Norman Romanesque church, but with the walls covered with shining, gilded Byzantine mosaics, the arches pointed, like those in the Islamic world, and the ceiling patterned in an Arab muqarnas style.

On top of this, Roger's reign also produced the Tabula Rogeriana, the Kitab-al-Rujar, the Book of Roger, a world atlas commissioned from the geographer Muhammad Al-Idrisi, originally from Ceuta, now a Spanish exclave on the coast of Morocco. It's quite tangential, but I'm a map guy so I'm bringing it up anyway. It is inspired by the work of the ancient Greco-Roman-Egyptian astronomer and geographer Ptolemy, and as such divides the habitable parts of the Northern Hemisphere into seven "climes", split along lines of latitude, based on the length of the longest day of the year, while the equatorial and polar regions were considered too hot and too cold respectively to live in. Al-Idrisi further subdivides each clime into ten different sections, meaning the atlas has a total of 70 maps, all of different parts of the world, each with a commentary describing the region's physical and human geography. And while it was commissioned by a Western Christian King, the atlas is very much a product of the Islamic World. Its labels and commentary are in Arabic, and the maps are oriented with South at the top, as was standard practice in the medieval Islamic world, since South is the direction to Mecca from Damascus, the old Umayyad Capital.

Roger II's daughter, Constance, married Henry VI, King of Italy and King of Germany, in 1186. In 1191, Henry VI was elected Holy Roman Emperor, making Constance the Holy Roman Empress, and then in 1194, after her great-nephew died aged 14, having reigned as King of Sicily for 8 months, Constance became Queen of Sicily as well, ruling jointly with her husband, who controlled a domain stretching all the way from the Baltic to Malta.

Constance and Henry's son, Frederick, was born the same year. According to the chronicler Salimbene di Adam, the Abbot Gioacchino da Fiore prophesied to Henry:

"O Prince, your boy, your son, your heir is perverse and evil. Ha! God! He will shake the earth and shall crush the saints of the most High"

But then, Gioacchino da Fiore also predicted that the year 1260 would mark the start of something called "the age of the Holy Spirit", when the Church would renounce its material wealth, Muslims and Jews would all convert to Christianity, and the world would remain at peace until the last judgement - a prophecy which, as you might have noticed if you've been keeping up with the events of the last 765 years, has not proved completely accurate, so I'm not how much we can really read into this.

Henry died in 1197, and Constance died in 1198. She was succeeded on the Sicilian throne by her son. If you've ever met a four-year-old, it will come as no surprise that Frederick was not well-suited to the duties of Kingship, so this was handled by the Pope, Innocent III, and then by a succession of obscure and scheming German and Italian officials until 1208, when, at the age of 13, Frederick was deemed to be old enough to rule in his own right, and tasked with asserting his authority over his Kingdom.

In 1209, Otto IV was crowned Holy Roman Emperor by the Pope, promising not to interfere with the parts of Italy ruled by either the Pope or Frederick. He immediately proceeded to invade the Pope's territories in Ancona and Spoleto, and claimed sovereignty over Frederick's mainland Italian territories.

After he marched to Rome itself in an effort to assert his authority over the pope in the long-running Investiture Controversy over which of the Pope or the Emperor had the authority to appoint bishops, the Pope excommunicated the Emperor, and in 1210 Otto invaded the Kingdom of Sicily. In 1211, rebellious German nobles, fed up with Otto ignoring the north of the Empire and spending all his time in Italy, elected Frederick, now 16 years old, as King of Germany and King of Italy.

He spent the next few years disputing his position as King of Germany with Otto, who in practice controlled most of the North of the Country, and in 1217, the Fifth Crusade departed for Egypt, which was under the control of the Ayyubid Sultanate.

Frederick had promised to go on this crusade, and the Pope had repeatedly postponed it to allow him time to resolve his domestic disputes with Otto, but in the end the crusaders left without him. In 1219, when the crusade was going well, the Ayyubids offered a very favourable peace, including ceding the city of Jerusalem, but the crusaders refused, expecting Frederick to show up at any moment with a huge army which could secure an even better peace. In the end, the crusaders left with nothing after the Sultan's forces opened a sluice gate on the Nile to flood their camp.

In 1220, while the fifth crusade was still in Egypt, Frederick finally managed to get himself crowned Holy Roman Emperor, and then set about attempting to secure direct control of the Kingdom of Sicily, where much of the real power had been ended up in the hands of various minor nobles while he was a kid. He established a powerful navy, expelled Genoese merchants and seized their assets, and deported Sicily's remaining Muslim population, likely around 60,000 Muslims, to the town of Lucera on the Italian mainland, where they were allowed to practice their religion freely in return for being heavily taxed, and large numbers were recruited into Frederick's army and his personal bodyguard.

After his coronation as Emperor, Frederick kept promising to go on a crusade, and in 1225 he married the 13-year-old queen Isabella II of Jerusalem, which meant he was now not only King of Sicily and Holy Roman Emperor, but also King of Jerusalem, and had a clear vested interest in expanding the territory of what was now his own Kingdom, and reconquering its former capital that gave it its name.

In 1227, Frederick was finally ready to go on a crusade, and the crusaders set sail from Brindisi, before almost immediately coming back to port, 50 miles along the coast in Otranto, where Frederick disembarked, suffering from some unspecified infectious disease that had broken out on the ship. He sent envoys to the Pope explaining why he couldn't go on the crusade, but the Pope by this point was tired of his shit and excommunicated him, despite him actually having a legitimate reason this time for not going on the crusade.

The following year, Frederick actually did depart for the Holy Land, only this time he was under excommunication, so wasn't officially allowed to go on a crusade. The pope excommunicated him again, on top of the existing excommunication.

In the Holy Land, the Sixth Crusade involved almost no actual fighting. Instead, Frederick was able to take advantage of the fact that the Ayyubid Sultan Al-Kamil was tied up with a civil war with his nephew and didn't want another war at the same time, and negotiated to get back Jerusalem, with the Muslims retaining control of the Al-Aqsa Mosque, and the treaty expiring after ten years. This was extremely unpopular with the Muslims, and controversial among the Christians - either it was a great achievement to get back Jerusalem without even having to fight for it, or it was a cowardly compromise that left Jerusalem very difficult for the Templars and Hospitallers to defend. And the fact that Frederick had done it without permission from the Pope, while he was doubly excommunicated, certainly didn't help matters.

On March 17 1229, Frederick went into the Church of the Holy Sepulchre and, since the Patriarch refused to crown an excommunicate, the Emperor put the crown on his own head. This was especially egregious because Frederick had only been King of Jerusalem in right of his wife, Isabella, and she had died the year before, meaning legally, their 11-month-old son, Conrad, was the actual King of Jerusalem.

Frederick returned to Sicily, and recovered the territory that had been lost to an army led by the Pope while he was away. He even managed to get the Pope to lift both excommunications. He spent the next few years fighting various obscure wars against Medieval Italian city states, and defending his Empire against the Mongol invasions. In 1245, he got excommunicated again, this time partly for just generally having the sort of beef with the pope that Holy Roman Emperors usually had, and also for his unusual friendliness towards Al-Kamil. The Pope went so far as to describe him as "a friend of Babylon's Sultan."

Finally we can start moving towards why we're talking about this fascinating guy in this episode.

One of the most interesting things about him is his intellectual life. One of the intellectuals he kept around him was the mathematician and astrologer Michael Scot, with a name that sounds far too prosaic for a Medieval Sorcerer. He was originally from the Scottish Borders, and had learned Arabic in Toledo, conquered from its Muslim rulers by Alfonso VI of Castille in 1085, and studied the works of Aristotle that had been translated from Greek to Arabic in the 9th Century. He also translated the works of the 11th-century Persian philosopher Ibn Sina (or Avicenna) and the 12th-century Andalusian philosopher Ibn Rushd (or Averroes) from Arabic to mLatin. At Frederick's court, Michael Scott studied astronomy, astrology and alchemy, and also translated Frederick's communications with Arab rulers. According to Dante Alighieri, he eventually ended up in the 8th circle of Hell, along with other sorcerers and False Prophets, forced to walk backwards with his head turned round through 180 degrees to face the wrong way as a mockery of his attempts to tell the future.

There was another notable scholar employed at Frederick's court, one who does not appear in Dante's Inferno, but who is in fact far better known nowadays. His best known achievement is the result of a thought experiment in which he worked out the number of breeding pairs of rabbits in a population under implausible ideal conditions every month. If the rabbits are immortal, and reach maturity after a month, and each pair of adult rabbits gives birth to two rabbits every month for their entire eternal lives, and the ratio of male and female rabbits is exactly 50:50, and all the adult rabbits actually have sex (including with their siblings if necessary), then this mathematician realised that, starting from a single pair, the number of breeding pairs of rabbits in the population every month would be the sum of the numbers the two previous months, forming the sequence 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 235, etc.

While this sequence of numbers turned out over the centuries to have all sorts of applications, and is probably the main reason you've heard of him, Leonardo Bonacci, sometimes referred to as filius Bonacci, ("son of Bonacci" in Latin), which became abbreviated to Fibonacci, has an even more important legacy, one that you use far more than even the Fibonacci sequence, and one very appropriate to someone working in the relatively cosmopolitan trans-mediterranean environment of Medieval Sicily.

On his visits to the trading post of Bugia, now Béjaïa in Arabic, on the coast of present-day Algeria, where his father worked as a customs official, he learned a system for writing numbers that had been ubiquitous in the Islamic world for centuries by this point, and that had been used in India for much longer still. In this system, any number can be represented with a combination of ten digits, which on their own represent integers up to 9. Moving a digit one space to the left, filling in the gaps with zeroes (another new concept acquired from India via the Islamic world), multiplies its value by 10. Bonacci correctly realised that this system is far more efficient for doing pretty much anything than the Roman Numerals used in the West up to that point (seriously, I'm often very impressed by how much the Romans managed to pull off with such a preposterous number system), and used it in his Liber Abaci, or "book of calculation", from where it caught on and became the main way that Europeans wrote numbers, even to this day.

Alongside his Italian mathematician and his Scottish wizard, Frederick was also something of a scientist in his own right. He was fascinated by animals, and notorious for his menagerie, with elephants, lions, leopards, monkeys, a polar bear that the King of Norway sent him, and probably the first ever giraffe in Europe since Roman times. He apparently used to hunt using leopards and panthers, and one time he was visiting a monastery in Verona and showed up accompanied by an elephant, five leopards and twenty-four camels.

And among all this, his real obsession was birds. He was a passionate falconer, he collected gyrfalcons, among the most prized of all hunting birds, all the way from the Norse settlements in Greenland. He had a marsh near Foggia where he kept water birds in conditions approximating their natural habitats. He even appears to have owned a sulphur-crested cockatoo, given to him by the Ayyubid Sultan, that must have come all the way from New Guinea, traded from one merchant to another or received as tribute, plunder or a diplomatic gift by a series of monarchs. He went so far as to write an entire book, De Arte Venandi cum Avibus, or On the Art of Hunting with Birds.

Large parts of the book are, as suggested by the title, concerned with the practicalities of falconry, which the title of the first chapter describes as "an art more noble than other forms of hunting", but the book is also much broader in scope, covering all sorts of ornithological topics, certainly influenced by Aristotle's Book of Animals, which Michael Scot translated, but at the same time deeply critical of Aristotle, with Frederick writing

"In his work, the Liber Animalium, we find many quotations from other authors whose statements he did not verify and who, in their turn, were not speaking from experience. Entire conviction of the truth never follows mere hearsay"

On the Art of Hunting with Birds is especially notable for its description of the migration of birds, relying on the division of the world into seven climatic zones used by Al-Idrisi at the court of Frederick's grandfather Roger II, and for his refutation of the common medieval belief that barnacle geese are not hatched from goose eggs laid by other barnacle geese, but are instead spontaneously generated from goose barnacles or, as Frederick says, worms that form in the hulls of rotting ships in the Arctic (which meant that Catholics were allowed to eat them on Fridays, since they weren't really proper animals).

"It is said that in the far north old ships are to be found in whose rotting hulls a worm is born that develops into the barnacle goose. This goose hangs from the dead wood by its beak until it is old and strong enough to fly. We have made prolonged research into the origin and truth of this legend and even sent special envoys to the North with orders to bring back specimens of those mythical timbers for our inspection. When we examined them we did observe shell-like formations clinging to the rotten wood, but these bore no resemblance to any avian body. We therefore doubt the truth of this legend in the absence of corroborating evidence. In our opinion this superstition arose from the fact that barnacle geese breed in such remote latitudes that men, in ignorance of their real nesting places, invented this explanation."

I might do a whole miniseries about Frederick II at some point, but the important point here, really, for our story, is that Frederick II was an intellectual, and a curious man, and understood the importance of carrying out experiments to test scientific claims for yourself.

And this brings us to the story that qualifies him for inclusion in this miniseries.

The only source for this story is the Chronicle written by the Franciscan Friar Salimbene di Adam, who says that Frederick carried out an experiment similar to that of Psamtik.

"He wanted to test what kind of language children would have when they grew up, if they spoke with nobody. And therefore he ordered that stewards and nurses should give milk to the children that sucked their breasts, and bathe and clean them, but by no means should they show them affection or talk to them. By these means, he wanted to find out whether they would speak the Hebrew language, which was the first, or Greek or Latin or Arabic, or even the language of the parents who gave birth to them.

But he laboured in vain, because the children or infants all died. Indeed, they could not live without clapping and gestures and happy faces."

Salimbene includes this along with several other anecdotes about Frederick's villainy, that he refers to using the word "superstitiones", which the translation I'm looking at by Joseph Baird, Giuseppe Baglivi and John Kane, translates as "idiosyncracies". These are as follows:

He had a clerk's thumb cut off because he spelled his name Fredericus, with an e, rather than Fridericus, with an i. Bear in mind that Fredericus and Fridericus were both generally completely correct Latinisations of the German name Friedrich, so this is purely a matter of personal preference rather than correctness.

He made a blasphemous joke when he arrived in the Holy Land about how if God thought this was the best place to put his promised land for the Jews, he'd clearly never seen the Kingdom of Sicily.

He got a man called Nicholas, who was quite impressively good at diving, to repeatedly dive to the bottom of increasingly deep parts of the straits of Messina until he didn't come up again. Salimbene never says whether this was a scientific experiment or if Frederick just thought it would be funny.

He fed two men a big meal, and then got one to go hunting and the other to go to bed. A few hours later, he had them disembowelled, determining that the one who went to bed had digested the food better.

He asked the astrologer Michael Scot how far his palace was from heaven. After getting an answer, the two of them went on holiday for a few months, and while they were away, Frederick had a team of architects lower the room of the palace where Scot had performed his calculation. When they got back, he asked Scot the same question, and Scot, not realising that the room had been lowered, answered that “either heaven had risen or the earth had sunk”, which proved the astrologer was for real.

He kept a man sealed in a barrel until he died, hoping to prove that the soul died with the body. Salimbene doesn't say what exactly Frederick was expecting to observe, but most people writing about it in modern times suggest that the idea was that, if the soul left the body after death, he would see the man's soul physically leaving the barrel. Here Salimbene seems less concerned with the experiment's highly unethical methodology than with its blasphemous hypothesis.

Salimbene says all this was alongside "many other idiosyncracies: idle curiosity, lack of faith, perversity, tyranny, and accursedness".

It's genuinely hard to say how much truth any of this had. Salimbene obviously absolutely despised Frederick, describing him as

"an evil and accursed man, a schismatic, a heretic, and an Epicurean, who defiled the whole earth, because he sowed the seeds of division and discord in the cities of Italy, which has lasted up until the present time".

Saying of him:

"But the Emperor Frederick knew nothing, nor wished to know anything, about proper deference, because of his meanness and avariciousness. In fact, in the end he always slandered, confounded, or killed all his friends so that he could obtain all their possessions and treasure for himself and his sons.”

He even once wrote a treatise entitled "The Twelve Evils of the Emperor Frederick".

The word "Atheism", or its cognates, didn't exist until the 16th century, but this is essentially what Salimbene is accusing Frederick of when he calls him an "Epicurean". Nowadays, the name of the ancient Greek philosopher Epicurus is mostly associated with his ethical philosophy advocating pleasure-seeking as the supreme good, but in the Middle Ages, the term Epicurean was associated instead primarily with the philosopher's emphasis on materialism, and his rejection of the role of the Gods in the organisation of the Universe. There was a popular moral panic in Medieval Europe about a widespread and serious Epicurean movement, especially rejecting the immortality of the soul, but there's no serious evidence that such a movement actually existed, beyond vague rumours like Salimbene's.

Other people also accused Frederick of being an atheist. Pope Gregory IX, in his 1239 papal bull excommunicating the Emperor for the third time, accused him of saying

"that the whole world is deceived by three impostors: Moses, Jesus and Mohamed"

Frederick's adviser Pietro della Vigna was even rumoured to have written a book called "Concerning the Three Impostors", where the impostors in question are the three founding figures of the Abrahamic religions. He was the first of several people over the subsequent centuries to be accused of writing this specific scandalous tract, including Giovanni Boccaccio, Niccolo Machiavelli, Frederick himself, and Frederick's grandfather, the Emperor Frederick Barbarossa (likely a result of confusion with his grandson). There is no evidence that such a text ever actually existed.

As an aside, Pietro della Vigna would subsequently be accused of some unclear crimes against Frederick, and the Emperor had him blinded and imprisoned. He died in prison in mysterious circumstances, possibly suicide, or possibly not. Dante described him in the 7th circle of Hell, transformed into a tree as punishment for his supposed suicide.

And Gregory's successor, Innocent IV, also joined in, calling Frederick the "precursor to the antichrist".

For historical reasons, it's not really all that surprising that Salimbene had beef with Frederick, and to explore those reasons we're going to have to talk a bit about the convoluted political history of the Medieval Holy Roman Empire, in particular the Investiture Controversy.

You could go into a lot of detail about the Investiture Controversy that I won't, because it's not particularly relevant to this podcast (other podcasts absolutely have. Check out Wittenberg to Westphalia by Ben Jacobs, or The History of the Germans Podcast by Dirk Hoffman-Becking), but in brief, this was a dispute in the 12th-century Holy Roman Empire over whether the Pope or the Emperor had the authority to appoint bishops. The house of Welf (Guelfo in Italian) had supported the Pope. The house of Hohenstaufen, of which Frederick was a member, whose nickname, the Ghibellines, derived from the castle of Waiblingen in Swabia, (Ghibellino in Italian) had supported the Emperor. The House of Welf and the House of Hohenstaufen, the Guelphs and the Ghibellines, spent the next couple of centuries fighting over who got to be the Holy Roman Emperor.

Frederick's predecessor in the role, Otto of Brunswick, was a Guelph who was deposed when he fell out with the Pope. Frederick spent a large part of his reign participating in the wars between the Guelphs and the Ghibellines, on the Ghibelline side, and as such was deeply unpopular with supporters of the Guelphs.

Salimbene was a native of the city of Parma, where Parma Ham comes from, in the Northern Italian region of Emilia, which had been run by the Ghibellines, but was taken over by Guelphs in a coup in 1243, supported by the Pope. The city was also a member of the Lombard League, a confederation of Northern Italian city states formed in 1167 to resist threats to their autonomy from the emperors (more information in Mike Corradi's podcast A History of Italy). In 1248, Frederick besieged the city, but was defeated by the Lombard League.

Frederick waging war against his hometown is certainly one reason for Salimbene to have beef with him, and the other reason is that Salimbene was a member of the Franciscan order.

The Franciscans were (and indeed still are) an order of friars founded in 1209 by St Francis of Assisi (a contemporary of Frederick II who, unlike him, had actually gone on the 5th crusade, and was involved in a strange incident where he met the Sultan and attempted to persuade him to convert to Christianity - the Sultan very politely refused). After the Pope had excommunicated Frederick in 1239, the Emperor had responded by expelling the Franciscan and Dominican orders of friars from Lombardy in Northern Italy. The Franciscans (as might be expected of a Catholic religious order) fell in firmly behind the Pope in his rivalry with Frederick, and supported the Guelph coup in Parma in 1243. So as a Franciscan from Parma, it's hardly surprising that Salimbene hated Frederick, and this sort of gives him an incentive to tell us scandalous rumours about him that aren't necessarily factual.

As well as Frederick's reported cruelty, the same can be said, to an extent, of his unorthodox religious views. In the Middle Ages, the accusation of being an "Epicurean", to use Salimbene's word, who doesn't believe in the immortality of the soul, was one of the most scandalous things you could say about someone. Alleging that your enemies were heretics, or even outright atheists, was the perfect way to discredit them. On the other hand, Frederick genuinely does seem to have been more religiously open-minded than was normal in his time. The way he was comfortable doing business with Muslims, and the concessions he made with the Sultan in the 6th Crusade, enabling him to become King of Jerusalem, as well as his ongoing rivalry with the Pope, do sort of suggest a man who was not willing to let his loyalty to Christendom get in the way of advancing his own interests, so it's certainly very plausible that he might not have taken his religion as seriously as would normally be expected of a Medieval King.

At the end of the day, with the things that we only know from Salimbene, we don't really have any way of ever knowing what's true, what's exaggerated, what's a retelling of a widespread rumour, and what's simply fiction invented by the friar. It's comparable to how if, in 800 years time, Fox News was the most detailed surviving source of information about early 21st-century American politics, historians at the time might conclude that Barack Obama was a Muslim Communist with a secret plan to destroy America. The introduction to the translation of Salimbene's Chronicle that I'm using makes the point that Salimbene is generally right about things that can be cross-checked against other sources, but personally I'm not sure how much we can read into that. Generally writers who are in the business of writing propaganda know what they can and can't get away with lying about, and it's generally easier to get away with inventing stories about things that someone did in private than about well-documented historical events. Besides, how would Salimbene even have known about these things? He never met Frederick, and he doesn't say what his sources were. If he himself wasn't inventing the stories, he would have been hearing them at least second hand. It feels quite plausible to me that Salimbene was repeating widely-circulating rumours that he was predisposed to believe given his existing dislike of Frederick.

Frederick died in 1250, and would end up, according to Dante, in the 6th circle of Hell with the other Epicureans, imprisoned in a burning tomb to symbolise his refusal to accept his soul's immortality. He's honestly interesting enough that I think at some point I might end up doing a whole miniseries about just him, if I can find aspects that haven't already been thoroughly covered by the History of the Germans podcast and the History of Italy podcast, which both had multiple episodes about this extraordinary figure.

I guess now it's time to talk about what other people were saying around the same time about the question Frederick was trying to answer.

At the end of the last episode, I briefly mentioned an idea about the origin of language that originated among Jewish scholars in antiquity but would become popular throughout Europe after the Romans adopted Christianity - that is, that in the Garden of Eden, God, Adam and Eve (and presumably the snake, although I don't know of anyone specifically mentioning it in this context), all spoke Hebrew. Salimbene alluded to it in his description of Frederick's experiment - "The Hebrew language, which was the first".

St Augustine of Hippo, probably the most influential Christian thinker of classical antiquity, endorsed this theory. He wrote that Hebrew is named after the Biblical patriarch Heber, the great-great grandson of Noah, via his eldest son, Shem (the namesake of the Semitic languages, a family which includes Hebrew, as well as Arabic and Amharic), who refused to help with building the tower of babel and thus was allowed to retain his own native language (although given that this language was now of no use to communicate with anyone else, it's not clear how much of a reward this actually was). Augustine points out that the language became named after Heber because before that point there was no need to give it a name, because there were no other languages that it needed differentiating from. To be clear, while Heber is indeed mentioned in the Bible as a descendant of Noah and an ancestor of Abraham, the story about him refusing to participate in the building of the tower of the Babel (and thus the primacy of Hebrew as humanity's original pre-Babel language) is purely a headcanon.

Then a couple of centuries later the same idea is expressed by the 7th-century Spanish scholar Isidore of Seville, another saint, and one of relatively few important intellectual figures from the period of European history that you can make a lot of people very angry by calling the Dark Ages. He's best known for his work the Etymologiae, in which he attempted to summarize all of human knowledge in 20 chapters, with titles including "Rhetoric and Dialectic", "Books and Ecclesiastical Offices", "God, Angels and Saints", "The Human Being and Portents", "The Cosmos and its Parts", "Stones and Metals", and "Provisions and Various Implements".

Etymologies, that give the book its title are the main subject of just one of these twenty books (although other etymologies are scattered throughout), which consists of a list of several hundred Latin words with questionable claims as to their origins. For example:

"The walking stick (baculus) is said to have been invented by Bacchus, the discoverer of the grape vine, so that people affected by wine might be supported by it."

Or that the Latin words ius meaning "broth" and ius meaning "law" (cognates of "jus" and "justice" respectively) are really the same word because broth "is the determining factor in the seasoning of cooking."

Or that the Latin word for bread, panis, comes from the Greek word pan, meaning "all", "because it is served with all food, or because all living creatures crave it".

At the start of Book 9, on "Languages, nations, reigns, the military, citizens and family relationships", Isidore discusses the origins of language. He mentions Heber, but only as the etymology of the Hebrew nation. However, he does describe the story of the Tower of Babel, and argues that Hebrew was the original language before God confused everyone's languages. He also lists it as one of three "sacred languages", the others being Latin and Greek, as a result of them being the languages used in the multilingual inscription saying "Jesus the Nazarene, King of the Jews", that the Gospel of John says was written on the cross when Jesus was crucified. In western art it's usually represented by the abbreviation "INRI", for the Latin "Iesus Nazarenus, Rex Iudaeorum". Of these, he says that

"Greek is considered more illustrious than the other nations' languages, for it is more sonorous than Latin or any other language."

While emphasising that Hebrew was the language of humanity before the Tower of Babel, Isidore doesn't make a definite claim as to what language God spoke in the Bible, although he points out that some people say it's Hebrew, and says that God nowadays speaks to people in their own native language:

"It is hard to determine what sort of language God spoke at the beginning of the world, when he said "Be light made," for there were not yet any languages. Or again, it is hard to know with what language he spoke afterwards to the outer ears of humans, especially as he spoke to the first man, or to the prophets, or when the voice of God resounded in bodily fashion when he said "Thou art my beloved Son." It is believed by some that the language in these places was that single one which existed before the diversity of tongues. As for the various language communities, it is rather believed that God speaks to them in the same language that the people use themselves, so that he may be understood by them."

Getting up to date with Frederick, we get to someone you've probably heard of, not least because he's already featured in this episode on account of his descriptions of the afterlives of three of this story's characters.

Some time in the early 14th century, the Florentine poet Dante Alighieri wrote an essay titled De Vulgari Eloquentia - "On Eloquence in the Vernacular" - where he argued for the merits of writing in vernacular languages, in particular his own Tuscan dialect, at a time when Italians more often wrote high-brow literature in Latin. The most interesting part of the essay, and the most relevant here, is his remarkable discussion of the history of Europe's languages.

According to Dante the first people who settled Europe spoke a language with three dialects. Speakers of one dialect settled in Greece, and became the Greeks, speakers of another dialect settled in Southwestern Europe, and their dialect gave rise to what we now call the Romance languages. The third dialect's speakers populated Northern Europe, and their dialect gave rise to the Germanic languages, the Slavic languages, and Hungarian (this doesn't line up with modern linguistics, where the Germanic, Slavic, Romance and Greek languages are all part of the same Indo-European family, and Hungarian has absolutely nothing to do with any of them).

Dante further subdivides the Romance languages, based on their words for Yes - all of which are a result of different workarounds to deal with the fact that Latin didn't really have a word for Yes. There are the languages that say si, from the Latin sic, meaning "thus", or "indeed" - that is, the various forms of Italian (He doesn't acknowledge the existence of Spanish at all, I guess because Spain was mostly ruled by the Moors at the time), the languages that say oïl, which was a medieval precursor to the French oui, and comes from the Latin hoc ille, meaning something like "this is it", and the languages that say oc, from the Latin hoc, meaning "this" - used in Occitan (which derives its name from the word), the old language of Southern France, closely related to Catalan, that was at Dante's time one of the Mediterranean's major literary languages, but after centuries of decline and deliberate suppression, is now a small, endangered minority language. I don't know if Dante knew about Romanian at all, which uses da (most likely borrowed from a neighbouring Slavic language), and the oldest known texts in Romanian are from the 15th and 16th centuries, so it's not that surprising that he doesn't mention it.

This is a remarkably early, and admittedly fairly rudimentary attempt at a task that would be very familiar to modern linguists - that is, attempting to investigate the early history of humanity based on the similarities and differences between languages, but this starts from an original point of spontaneous diversity produced by a divine miracle at the Tower of Babel, and as such can tell us nothing about the language of Adam. That said, modern comparative linguistics is also limited in its ability to go back beyond a certain point. Linguists can have a pretty good go at using modern languages and languages within written history to reconstruct proto-languages that were spoken much earlier, but the limits of reconstruction by comparative linguistics are a few thousand years, a small fraction of the time for which humans have presumably been using language.

For all the modernity of some of his ideas, Dante is in other respects very medieval. And he follows Augustine in firmly endorsing the claim that Hebrew was the language spoken in the Garden of Eden, and that Heber, the ancestor of the Hebrews, refused to help build the Tower of Babel, and was exempt from the confusion of languages that resulted. He claims that the Hebrew language, uniquely among human languages, is immutable, and that the divergence of other languages between geographically-separated peoples, that he very reasonably describes, was set in motion by God's punishment of the builders of the Tower of Babel, with a separate language being assigned to the workers employed in each role in the Tower's construction.

A few years later, Dante would go on to write his best known work, The Divine Comedy. And he seems to have changed his mind on the immutability of the Hebrew Language. In the third part, Paradiso, after Dante has visited Hell and Purgatory, he is taken on a tour of Paradise by Beatrice - generally considered to be inspired by Beatrice Portinari, a banker's daughter with whom the poet was obsessed, despite having apparently only met her twice. Paradise here is based on the Celestial Spheres of Aristotelian cosmology, consisting of nine spheres in total - the planets, minus Uranus and Neptune, which hadn't been discovered yet, Pluto, which also hadn't been discovered yet, meaning there were no arguments about whether or not to include it, and Earth, which wasn't counted as a planet in a geocentric system, and plus the Sun and Moon, as well as the sphere of fixed stars outside the planets, and the ninth sphere, which consists of angels circling around God, the prime mover, who appears as a point of light, and from there to the Empyrean, home to God himself.

Dante and his crush gradually move upwards through the spheres, like Inferno in reverse, meeting various historical figures who the author approved of, categorised according to the supposed astrological associations of the planets in their respective spheres. When he gets to the eighth sphere, the Sphere of Fixed Stars, he meets a range of saints, apostles and prophets.

Among them is Adam, but he does not tell Dante that he spoke the same immutable Hebrew language in which the Old Testament would go on to be written. Instead, he describes even his own language as in perpetual flux, so that even by the time of the Tower of Babel it had already altered beyond recognition.

"The language that I spake was quite extinct
Before that in the work interminable
The people under Nimrod were employed;

For nevermore result of reasoning
(Because of human pleasure that doth change,
Obedient to the heavens) was durable.

A natural action is it that man speaks;
But whether thus or thus, doth nature leave
To your own art, as seemeth best to you.

At the same time as Dante was writing, there was another school of linguistic thought thriving, not among Italian poets, but among logic nerds in the University of Paris, and they definitely did not accept that Hebrew was the default language of humanity, that children would naturally speak in an experiment like that of Psamtik or Frederick.

Modism flourished in the late 13th and early 14th centuries, so a couple of decades after Frederick's death, among mostly Northern European thinkers such as Boethius Dacus ("Boethius the Dacian" - in fact from Denmark rather than Romania), Martinus Dacus ("Martin of Dacia", also not a Romanian but in fact another Dane called Morten Mogensen), and Thomas of Erfurt. Modists argued that there is a sort of Universal Grammar, a common structure to all languages, innately understood by all humans, and that the differences between actual languages are merely accidental. According to Modists, the structure of this universal grammar reflected the fundamental metaphysical structure of reality.

Modists argued that an object has actual properties - its modi essendi, or "modes of being", which are represented to our minds by means of the modi intelligendi, or "modes of understanding", which are in turn represented in grammar through the modi significandi, or "modes of signifying". The modists pointed out that the same object can be represented in language in different ways, often corresponding to different parts of speech, and these are its modi significandi. Thomas of Erfurt used the example of "White" (an adjective), "Whiteness" (a noun) and "to become white" (a verb).

This sort of gets round the objection raised by Hermogenes in Cratylus, that words can't have meanings that are fundamentally correct or incorrect because different people use different languages, by claiming that these differences are merely accidental, and that the universal grammar is what reflects deep metaphysical truths, and not the vocabulary of any particular actual language, which just arises by convention.

This position is not too different to that of Aristotle, the Greek Philosopher who the medieval scholastics viewed with an even more sycophantic reverence than they held for their co-religionist Augustine. He rejected out of hand the idea that any one particular language was in any sense more natural than any other, and likewise held that particular languages arise purely as a matter of convention among the members of a particular society.

Boethius Dacus describes this in a way that specifically alludes to a language deprivation experiment (although this time just a thought experiment, not actually torturing any babies).

"What is to be said to this, that if some people were fed in the wilderness, so that they never heard the speech of other humans, nor received any information about how to speak, they would naturally express their feelings to each other in the same way. Speech is indeed one of the natural functions, which is a sign that nature has placed in us a tool by means of which speech happens. And therefore, just like humans naturally have other natural functions, so they also have speech and even grammar, through which a person can express the intended concept."

Boethius Dacus argues that this innate ability is different from the ability to speak any one particular language.

"Yet behold, how although a Latin speaker doesn't understand Greek grammar or vice versa, this is because these are accidental forms of grammar maintained by teaching and not by nature."

He claims that, if we stripped away all the accidental features of language that people have ended up learning, there would be something left, an instinctive language common to all humans, that works just like any of the other things we know how to do instinctively. He says he elaborates further in his commentary on Aristotle's De Animalibus, but, to quote Sten Ebbesen, "the work has not been identified in any extant manuscript", so we have no idea what he actually said there.

And then we get Siger of Brabant, who presented something that has echoes of the position of the Epicureans on the actual origins of language (the actual followers of Epicurus from ancient Greece and Rome this time, not the largely fictional sect of atheists that lived rent-free in the minds of pious Medieval Catholics), arguing that in a situation where two people are completely isolated from all language, their innate capacity for language would lead them to associate each other's vocalisations with the things they were doing at the time. The example he gives, reminiscent of Psamtik's experiment, is how, if one of them holds out some bread, while making a noise, the other one will understand that that noise is the noise that represents bread.

An interesting point about what Siger says is that it highlights the importance of having more than one child in these experiments. This is something all the creators of language deprivation experiment rumours seem to have picked up on as well. I guess it makes a lot of intuitive sense. If there's only one kid they're not going to start talking because they don't have anyone to talk to. There's always an understanding that interpersonal communication is necessary for language to develop. Although in the accounts of the experiments, none of them actually explicitly mention the idea that the children would teach each other the default language. And if there is a default language, why would they need to teach it to each other, like how Siger describes? The consistent use of multiple children might suggest a persistent belief that some learning is necessary to use language, even if only to sort of unlock the default language which they already have an innate knowledge of.

Medieval scholars mostly believed that people born deaf can't learn to speak (this is in fact wrong, and many congenitally deaf people in fact do learn to speak, but by actively learning it by means other than hearing, not because they have innate knowledge of a particular language). Obviously deaf people can't speak Hebrew (unless of course they have actually learned Hebrew). As the 14th-century Dutch philosopher Marsilius of Inghen said, quoted by Sten Ebbesen:

"But then there is a doubt about a boy who was not born deaf, but had been absconded until adulthood in a location to which no persons or person had access, which language such one would speak when reaching adulthood. Some have answered that he would speak the Hebrew language, because, they say, that is natural to us. But that is a frivolous, ridiculous and totally baseless answer. For if the Hebrew language was innate in every human being, certainly anyone of us would be able to speak that very language whenever he pleased, and people born deaf but with no tongue impediment would possess the Hebrew language."

If you remember the last episode, I talked about Plato's dialogue Cratylus, where two characters, Hermogenes and Cratylus, argue about whether words have inherent natural relationships to the things they signify, or whether the meanings of words are purely a matter of convention. While Boethius Dacus's Universal Grammar might have a real relationship to the structure of the natural world - reflecting the view of Cratylus, his position was that this could not be applied to individual words in actual spoken languages, which arose as a matter of convention, reflecting the view of Hermogenes. This idea of language as conventional became tied up with beliefs about the linguistic abilities of deaf people. Radulphus Brito, a French Modist active in the early 14th century (quoted by Sten Ebbesen) explains how:

"Speech is significative by convention due to a common agreement between several people. But a congenitally deaf person cannot participate in such a concord and agreement with other people. Consequently, he cannot produce conventionally significant word-sounds, and so he cannot speak."

Apparently the French scholastic philosopher John Buridan, best known for his ass, made the strange argument that learning a language purely in its written form just didn't count as learning a language (strange considering these people did all their work in Latin, which had had no native speakers for centuries). And as far as I can tell, nobody in the Middle Ages seems to have taken the slightest interest in writing about sign languages. While it would have been difficult for large-scale sign languages to have developed without substantial communities of deaf people communicating with each other, small-scale home sign systems presumably existed, maybe used by one deaf person to communicate with people they knew, or probably sometimes within a family or even a village with an unusually high rate of congenital deafness for genetic reasons. Indeed, Plato's dialogue Cratylus, that I talked about in the last episode, contains one of the earliest known written references to sign languages used by deaf people, with Socrates saying:

"And let me ask another question: if we had no faculty of speech, how should we communicate with one another? Should we not use signs, like the deaf and dumb? The elevation of our hands would mean lightness; heaviness would be expressed by letting them drop. The running of any animal would be described by a similar movement of our own frames".

This demonstrates that, as we would expect, deaf people have been using sign language at minimum since the 4th century BCE (and I'd be very surprised if sign language wasn't many times older).

But at the time we're talking about we know almost nothing at all about them, and there seems to have been a prevailing consensus in Medieval Europe that deaf people were incapable of acquiring language. It wasn't until the 16th-century that the Spanish Benedictine monk Pedro Ponce de Leon established what is often considered the first ever school for deaf children, and he was focused primarily on teaching them to speak Spanish. There's some evidence that he developed a sort of fingerspelling, based on systems already used by monks who had taken vows of silence, but no record of him using or teaching an actual sign language. Indeed, the first known description in English (I couldn't find anything older from anywhere else) of any specific signs in such a language is from 1575, when the Parish register of St Martin's Church in Leicester described the wedding of a deaf man, Thomas Tillsye, to a woman by the name of Ursula Russell:

"The sayd Thomas, for the expression of his minde, instead of words of his owne accord used these signs: first he embraced her with his armes, and took her by the hande, putt a ring upon her finger and layde his hande upon her harte, and held his handes towardes heaven; and to show his continuance to dwell with her to his lyves ende he did it by closing of his eyes with his handes and digginge out of the earthe with his foote, and pulling as though he would ring a bell with divers other signs approved."

Despite all this, it doesn't seem to have been until the 18th century that educators started to think of sign languages as languages, with comparably sophisticated communicative power to spoken languages, with Charles-Michel de l'Épée founding the first school for the deaf using sign language as a medium of instruction in the 1760s, using a language based on the Sign Language that had already developed organically among Paris's deaf population.

But at the time in question, scholars seem to have mostly seen the actual act of producing "word-sounds", as Ebbesen chooses to translate the Latin word vox, so as to highlight that it is, in his words, "primarily a word qua phonetic entity", as a critically important feature of language. With this attitude, a sign language would be seen as something more like a sort of gestural communication, rather than a language comparable to spoken languages.

Salimbene's account of Frederick's supposed experiment also includes more possible results than Psamtik's experiment. We've got Hebrew, Latin, Greek, Arabic, and the language of the child's parents. I wonder if this reflects the multicultural nature of Medieval Sicilian society. There were at least four different communities in Frederick's Kingdom - the Latins, the Arabs, the Greeks and the Jews, all with their own ancient scriptures in their own sacred languages and scholarly linguae francae. In Christian tradition at the time, it was generally believed that Adam spoke Hebrew, and that was the same in mainstream Judaism. Most Muslims at the time believed that Adam spoke to God in Arabic, the language in which God also dictated the Qu'ran to Muhammad, and we've also got Greek, which ranks alongside Hebrew as the language of some of the oldest texts that anyone in Europe at the time could read (we should note that both Egyptian Hieroglyphs and Mesopotamian Cuneiform weren't deciphered until the early 19th century, so at this point the oldest literature anyone in the west knew about would have been the Old Testament, originally written in Hebrew, and the Homeric Epics, written in Greek). Latin's in there as well, which seems like an odd suggestion, given that the oldest Greek and Hebrew literature known at the time was far older than the oldest Latin literature, and nobody in the Bible spoke Latin until the Romans show up in the New Testament. Latin is not a suggestion you see often, but I guess it completes the set along with Greek, Hebrew and Arabic as the literary language of Sicily's Western Catholic population, which included Frederick himself, and had been running the island since the Normans conquered it from the Arabs, and also ranks alongside Hebrew and Greek as one of the languages that Isidore points out were used in the inscription on the cross where Jesus was crucified.

It's interesting here that, while Psamtik took it for granted that the children, regardless of their background, would speak the oldest language, Frederick has allowed for an additional possibility - that the children speak the language of their biological parents (from whom they were presumably separated before having the chance to hear them speak). In this case, presumably what must be happening is that a particular nationality or ethnicity has a particular language sort of genetically associated with it.

Obviously nobody in the 13th century knew about genetics, but in this case someone's native language would presumably be passed down from parents to children like other physical traits are passed down. Presumably Frederick realised, like the author of the Dissoi Logoi, that I mentioned in the last episode, with the thought experiment about a Greek and Persian child raised in each other's countries, that children who only ever heard a different language to the native language of their parents would grow up monolingual in that language, and would not know the native language of their parents at all - this would be a much easier experiment to conduct, and in fact would likely have occurred very frequently, in a multilingual society like Norman Sicily, with very high maternal mortality. Indeed, we can see this happening in the process of language death, not even necessarily through a process as dramatic as the death of the parents, but through the parents simply choosing not to speak their native language to their children. If children naturally spoke the native language of their parents regardless of having learned it, languages would never become extinct, and would presumably never change. All languages currently in existence must be identical to those allocated at the Tower of Babel if you believe that.

All this seems like the sort of thing that would be obvious to men as intelligent as Frederick and Salimbene. And indeed the same could be said of Hebrew. If everyone is naturally a native Hebrew speaker, why would people have to learn Hebrew? Why can't people speak Hebrew as easily as speaking their own native language? Marsilius of Inghen made the point forcefully, calling that idea "frivolous, ridiculous and totally baseless", and this seems to me like it ought to be obvious to absolutely anyone.

It's probably better to think of the position of the people who believe language deprivation experiments could yield an actual language as the result sort of as if people are born with a certain default language, whether that's Hebrew or Latin or Greek or Arabic or Phrygian or their parents' language, and then during the ordinary process of language acquisition that language is overwritten by the languages a child hears around them, so that the many languages of the world, that have developed from those created at the Tower of Babel, push out a child's innate knowledge of the Original Language. And that's why you have to construct weird experiments, to prevent that process of overwriting taking place.

It's also probably worth talking about another medieval idea, this time not necessarily about the language of Adam, or about the default language that children would speak without learning any other, but about the broader question of whether there is a language that is special, and set apart from others. For all the discussion about whether the Special Language was Hebrew or whether it was some sort of Universal Grammar, or whether there even was a Special Language at all, for some people, this language couldn't correspond to a regular human language. It had to be more esoteric.

The twelfth-century German Abbess and mystic Hildegard of Bingen didn't say anything specific about the origin of language, or about what language Adam spoke, but she did write about a mysterious, sacred language that she called "Lingua Ignota" - "The Unknown Language". The surviving written records of this, the oldest known example of a constructed language, consist of a glossary that Hildegard wrote, with translations of 1,011 words to Latin and German, and a single sentence, mostly in Latin, with a few Lingua Ignota words.

"O orzchis Ecclesia, armis divinis praecincta, et hyacinto ornata, tu es caldemia stigmatum loifolum et urbs scienciarum. O, o tu es etiam crizanta in alto sono, et es chorzta gemma."

The Latin translates as

"O orzchis Church, surrounded with divine arms, and adorned with hyacinth, you are the caldemia of the wounds of the loifolum, and the city of the sciences. O, o, you are indeed crizanta in high sound, and you are the chorzta gem."

Infuriatingly, the only one of these Lingua Ignota words that actually corresponds to one of the just over a thousand entries in the glossary, is loifolum, which seems to be a Latin-style genitive plural form of the word loiffol, which means "family", "clan", or "people". So the phrase "tu es caldemia stigmatum loifolum" means "you are the caldemia of the wounds of the nations" or something like that. The other words we can only guess at.

The exact purpose for which Hildegard intended the lingua ignota to be used is unclear, but Hildegard was clear that the language, and its associated writing system, the Litterae Ignotae, or "Unknown Letters", had been revealed to her by God, saying in a letter to Pope Athanasius III:

"But He Who is great and without flaw has now touched a humble dwelling, so that it might see a miracle and form unknown letters and utter an unknown tongue. And this was said to that little habitation: 'You have written these things in a language given to you from above, rather than in ordinary human speech, since it was not revealed to you in that form, but let him who has the pumice stone not fail to polish it and make it intelligible to mankind.'"

This is certainly in keeping with the rest of Hildegard's career - she was well-known for seeming to receive direct messages from God, and even wrote down sacred music that she said was divinely revealed.

Some of the words in Lingua Ignota seem to be related to German or Latin words, for example loifol sounds a lot like the German Leute, meaning people. There is also potential allegorical significance to some of the words - for example, Joseph L. Baird points out that the first word in the glossary, aigonz, meaning "God", starts with an A and ends with a Z, which could be a Latin-alphabet equivalent to the Alpha and Omega, the first and last letters of the Greek alphabet, that Jesus compares himself to in the Book of Revelation. The syntax seems to be mostly borrowed from Latin, although that may simply be because the only fragment we have is of a Latin text with Latin words swapped for Lingua Ignota words. It could be that, if we had a complete sentence written by Hildegard in Lingua Ignota, it would turn out to have its own independent grammatical rules, but we'll probably never know for certain.

Hildegard never claims that the Lingua Ignota is the language spoken by God, or that it was the language spoken by Adam, but she was clearly endorsing the idea that there is a special sacred language, and that this is different from Hebrew, Greek, Egyptian, Phrygian, Sanskrit, Arabic or any human language.

This sort of idea doesn't really fit into any kind of rational framework. It's very much a mystical idea that rejects attempts to analyse the world through reason in favour of a purported direct divine revelation. Of course, this method of knowledge-production is of little use to people who, unlike Hildegard of Bingen, do not regularly receive direct messages from God. But of course we don't know for certain the specifics of what Hildegard believed the lingua ignota to be, except that it's a language with some special divine significance. Maybe it was supposed to be the language God spoke to Adam, maybe it was the language used to communicate by the angels in heaven, maybe it was a language that God used to communicate with Hildegard. That's all lost to history.

So in summary what we've got in the High Middle Ages, as to the question of the origins of language, and the related question of the default language that a child would speak without exposure to language, is a sort of conventional Christian explanation - that Adam spoke Hebrew, as described by Augustine and initially by Dante, at least before the Divine Comedy. Then there's the Modist account - that current languages emerged by convention from an innate human language faculty, building on a universal grammar related to the deep structure of reality, and maybe we also have a visionary view like that of Hildegard, where God communicates in an esoteric language that bears no relation to any human language.

Frederick's experiment follows Psamtik's in presupposing that there is some language that is the default language (with the interesting addition that the default language might vary from one person to another according to their ancestry). There still isn't the possibility (at least, not mentioned by Salimbene) that the babies would be completely unable to acquire any language - and the possibility that they would speak an otherwise unknown language - perhaps an esoteric language like Hildegard of Bingen's Lingua Ignota, or the mysterious lost language of Adam that he describes to Dante in the 8th circle of Paradise, or a language that they had developed between themselves on top of a universal grammar, by associating each other's vocalisations with their gestures, like Siger of Brabant describes.

And that's where I'll leave off this time. Next time, we've got another King, and another language experiment.

I should also point out that the podcast now has a website, scienceapeculiarhistory.co.uk, where I'm going to be putting things like pictures, diagrams and sources for the episodes, as well as episode transcripts. If you have any feedback, questions, suggestions or corrections, you can message any of the podcast's social media channels or email admin@scienceapeculiarhistory.co.uk.