There has been some talk in the peak oil community about leaving some kind of legacy to post-peak societies – Lovelock's "scientific equivalent of the Bible" comes to mind, as well as John Michael Greer's essays. This is a subject worth discussing. It becomes increasingly obvious industrial society will undergo some kind of collapse. It is probably too late to prevent or even significantly delay it, but saving some of our civilization's achievements so that our successors – whoever they might be – are left with something else than ruins in the jungle is certainly something worth fighting for. The problem is that bequeathing them a hoard of textbooks written on acid-free paper won't be of much use if they don't understand them... as it is very likely to be the case.
Imagine, for instance, that your are a 31rst century scholar looking for information about antibiotics. After much research you have managed to find a book about it, stored in some half-forgotten library at the other end of whatever your country is called. After a long, dangerous journey across untamed wilderness you finally get to it and under the suspicious stare of some red-robed wiccan monk open it to read what for you amounts to :
Antibiootti on synteettinen lääkeaine, jota käytetään bakteerien tappamiseen tai kasvun hidastamiseen. Antibiootit ovat isäntäeliölle suhteellisen harmittomia, joten niitä voidaan käyttää bakteerien aiheuttamien tulehdusten hoitoon. Termiä käytettiin alun perin tarkoittamaan vain toisista elävistä organismeista saatuja kemikaaleja, mutta se on laajentunut tarkoittamaan myös synteettisesti valmistettuja molekyylejä. Antibiootit ovat pieniä molekyylejä (paino alle 2000 daltonia) eivätkä ne ole entsyymejä.
Languages change, and they never change more swiftly and more completely than during times of collapse. Of course, this is partly because writing obscure linguistic changes, even in the eyes of those who undergo them. The French language you may have learned at school if you had some time to waste is so different from what is effectively spoken in the street of Paris that it could be considered a completely different tongue, yet French people hardly notice it and continue to think that their language marks plural with a -s suffix while it does it through a combination of liaison and verb and article agreement.
That is not the whole story, however, and French is probably an extreme case. Most of the time, linguistic change tend to be delayed by the influence of ruling class dialect – generally quite conservative – of the administration, of the media and of the education system. The same influences tend also to erase local and regional differences and to replace them by an standard form of speech, generally based upon the upper class variety.
When societies collapse, however, so does the administration and all the institutions in charge of slowing language change. After peak oil, the net energy available to complex societies to fuel their complexity is bound to decrease, which means that there will be ever less resource to keep them working. Literacy becomes restricted to a shrinking minority as the education system unravels. Upper classes fragment and are gradually replaced by warlords with little interest in high culture and language. This is a slow process of course, more an orderly retreat than a route, but on the long run, it means that linguistic change undergoes a tremendous acceleration. Moreover, since the structures holding the society together can no longer be maintained, it begins to differentiate geographically, as it did historically with Latin, every power center developing its own version of the once common language and raising its local vernacular to the status of literary or state language.
Besides, as markets and polities fragment and human horizon shrinks, the chances that a local war or migration results in a snowballing language shift greatly increase. What is not possible in a modern nation state – a linguistic minority becoming a local majority and imposing its tongue – is clearly in a post collapse polity (or non-polity) and there is little doubt it will happen.
Contrary to what most people believe, there was no population replacement during the collapse of the Western Roman Empire. The invaders were few in number compared to local populations which had not changed since the neolithic. They just took advantage of the chaotic political situation to seize power, which sometimes, but not always, resulted in culture shift. That happened in Eastern Britain, where the incoming Anglo-Saxons were never a demographic majority but seemingly merged with the local aristocracies which converted, or were converted, to their culture while mostly retaining their tribal identity. The sub-roman British kingdoms mostly survived. They just changed nature - the Cantiaci became the Jutish kingdom of Kent, the Iceni became East-Anglia, the Regnenses became the Kingdom of Sussex – and it was not always the result of a violent take over. Hengest seized power through a coup, but Aelle was never a king while Cerdic and Penda were obviously Britons with British names.
History doesn't repeat itself but it often rhymes and similar events can definitely happen in the post-peak future, with the most likely heroes – remember, the English were quite a marginal people in the fifth century. America's most spoken language in the 31rst century may very well descend from Pensylvanian Dutch, Inuktikut or Navajo. While small tribal languages will probably die out or be swept away by mass migrations or political upheaval, some may experience the same kind of explosive growth English did historically. Widely spoken languages, among which English, are likely to differentiate into a chain of languages as dissimilar one from another as Romanian is from Spanish, but the can also wither away, shrink to small enclaves, some of which may be located outside of their original domain.
In fact, it is the whole linguistic desk peak oil and peak energy will reshuffle, as happened every time a major cultural or economic discontinuity has befallen the world. The consequences of the return to Babel won't be light – we are well placed in Brittany to know it. Even when it is slow and progressive, language shift is always a rupture. A deep rent open between the last generation of speakers and their descendants and whole parts of their heritage and culture is buried away, possibly forever. After the fall of the Western Roman Empire, the Catholic Church preserved the use of Latin but there is no guarantee a similar institution will do the same for French, English or Spanish and those tongues may go the way of Old Brythonic, Etruscan or Classic Maya, leaving cryptic inscriptions or weird-sounding loanwords as only traces of their existence.
If we don't preserve them, and a score of other less spoken ones which are often the only keys to very specific but very important local lores, all we will leave to our descendants will be the haunting memory of what we have lost