Does Esperanto evolve?

Question

Does Esperanto evolve over time like a normal language?

In normal languages it happens that some words change meaning over time or some grammar changes.

Answer 1

This is an interesting issue, and in a way Esperanto is a field study in linguistic evolution. Languages change because they are spoken within groups of people, and accidental or deliberate changes spread throughout the group to make sure everybody understands what it means. If groups are isolated (eg through geographical boundaries, but distance generally), changes do not get disseminated and dialects emerge which are sometimes mutually incomprehensible. So in some mountainous regions people from neighbouring valleys might not understand each other easily, even though they are not far away from each other, but geography means that there is little contact between the groups.

At some point these dialects diverge so much they become distinct languages. Kind of what happened to Latin as spoken in Spain, France, Italy, and Romania. Canadian French split off from "French French" and has since developed in a separate way.

Obviously, this would be a dangerous issue for Esperanto: English speakers of Esperanto speak amongst each other, but rarely with, say, Russian speakers (assuming less mobility/communication ability a hundred years ago). They would develop their own Esperanto dialects, presumably mixing in elements of their own first language (which they all share, so no comprehension problem). But then an English Esperantist would have difficulties talking to a Russian one.

One solution to this is to lock down the language, and discourage change. This is done to protect the mutual understandability between different Esperanto speaking communities. Hence the resistance to reforms, and a rather conservative attitude towards language change: without the conservatism, there would be a lot of different Esperantos, and the language would lose its raison d'etre.

The question is, how successful has this been? The natural pressure of language change versus the cultural lock down against it. I'm not enough of an Esperanto speaker to tell, but from what I have seen there is no difficulty in reading older texts.

Different parts of languages also change at different speeds. Words are more volatile than grammar, so while some new words have entered the language (after all, the world is changing constantly), grammatical change is much slower, and due to the few rules that Esperanto has, probably doesn't happen at all.

So, in conclusion, my answer would be yes, Esperanto does evolve, but no, not like a natural language, due to the constraints put upon it to preserve its integrity.

Answer 2

Esperanto is a normal language and does evolve. Even the Fundamento did not prevent that from happening, and there are a few cases in which words did "change meaning over time". With this answer I do not aim to cover the entire subject, but rather give one particular example that I find personally interesting.

The famous song Dek Bovinoj used the verb muĝi extensively. In the lyrics, it has the meaning "to moo", probably from influence of the French mugir and the English moo, which sounds like the first syllable of the word. Most Esperantists I know think muĝi means "to moo", perhaps because of Dek Bovinoj.

Yet, in literature, we find a different meaning. It often had a meaning similar to "to roar", and was applied to lions, thunder, crowds, the sea… It was probably from influence of the French and German translations of muĝi in the Fundamento: mugir | brausen, zischen. In the Esperanto-English Dictionary by Achille Motteau (1908, p. 96), muĝi is defined as "to roar (wind, waves, etc.). In the Plena Ilustrita Vortaro, the figurative definition fits with this usage.

However, the latter German translation in the Fundamento, zischen, does not fit at all with the other French and German translations: it means "to hiss", or rather "to sizzle", i.e. the sound of water when it gets in contact with a hot surface. Zamenhof often used the word in that meaning, and that is how he translated it in Russian (шипѣть, "to hiss") and in Polish (burzyć się, wrzeć, "to seethe, to boil") in the Fundamento. Since Russian was one of Zamenhof's native languages, we can suppoze that is how he originally conceived the word's meaning.

Here are a few examples:

… la muĝado de la patoj …

— La batalo de l’ vivo

Simile kiel fajro kontraŭ akvo

Batale sin defendas kaj muĝante

Ekstermi penas sian malamikon,

Tiele nun batalas la kolero

En mia brusto kontraŭ viaj vortoj.

— Ifigenio en Taŭrido

La patro prenis la plenan botelon kaj la korktirilon. Ho, estas io specialsenta, kiam oni tiamaniere la unuan fojon estas eltirata! La kolo de botelo neniam poste povis forgesi tiun solenan momenton; kiam la korko eliris, en la kolo de la botelo aŭdiĝis muĝo, kaj poste kluk-klukado, kiam la vino verŝiĝis en la glasojn.

— Fabeloj de Andersen 3

So here you have a word in Esperanto which has had three very different meanings throughout time.

Answer 3

Short answer: Yes.

Longer answer: Esperanto has both neologisms (new words entering the language) and archaisms (old words becoming obsolete). It also sees changes to its phonology, most notably the letter ĥ is becoming archaic (see this question and its answers What happened to the letter ĥ during the evolution of Esperanto from Zamenhof to our times?).

I am not aware of full fledged grammar changes, but I am sure that on the statistical level one can detect grammatical contructions that are becoming more popular over time and other ones that are becoming less popular.