Editing History of Esperanto (section)

== Evolution of the language ==
The [[Declaration of Boulogne]](1905) limited changes to Esperanto. That declaration stated, among other things, that the basis of the language should remain the {{lang|eo|Fundamento de Esperanto|italics=yes}} ("Foundation of Esperanto", a group of early works by Zamenhof), which is to be binding forever: nobody has the right to make changes to it. The declaration also permits new concepts to be expressed as the speaker sees fit, but it recommends doing so in accordance with the original style.

Many Esperantists believe this declaration stabilising the language is a major reason why the Esperanto speaker community grew beyond the levels attained by other constructed languages and has developed a flourishing culture. Other constructed languages have been hindered from developing a stable speaking community by continual tinkering. Also, many developers of constructed languages have been possessive of their creation and have worked to prevent others from contributing to the language. One such ultimately disastrous case was [[Johann Martin Schleyer|Schleyer]]'s [[Volapük]]. In contrast, Zamenhof declared that "Esperanto belongs to the Esperantists", and moved to the background once the language was published, allowing others to share in the early development of the language.

The grammatical description in the earliest books was somewhat vague, so a consensus on usage (influenced by Zamenhof's answers to some questions) developed over time within boundaries set by the initial outline ([[#References|Auld 1988]]). Even before the Declaration of Boulogne, the language was remarkably stable; only one set of lexical changes were made in the first year after publication, namely changing "when", "then", "never", "sometimes", "always" from ''kian'', ''tian'', ''nenian'', ''ian'', ''ĉian'' to ''kiam'', ''tiam'', ''neniam'' etc., to avoid confusion with the accusative forms of ''kia'' "what sort of", ''tia'' "that sort of", etc. Thus Esperanto achieved a stability of structure and grammar similar to that which natural languages enjoy by virtue of their native speakers and established bodies of literature. One could learn Esperanto without having it move from underfoot. Changes could and did occur in the language, but only by acquiring widespread popular support; there was no central authority making arbitrary changes, as happened with [[Volapük]] and some other languages.

Modern Esperanto usage may in fact depart from that originally described in the ''Fundamento'', though the differences are largely semantic (involving changed meaning of words) rather than grammatical or phonological. The translation given for "I like this one", in the sample phrases in the main [[Esperanto]] article, offers a significant example. According to the ''Fundamento'', ''Mi ŝatas ĉi tiun'' would in fact have meant "I esteem this one". The traditional usage is ''Tiu ĉi plaĉas al mi'' (literally, "this one is pleasing to me"), which reflects the phrasing of most European languages (French ''celui-ci me plaît'', Spanish ''éste me gusta'', Russian ''это мне нравится'' [eto mnye nravitsya], German ''Das gefällt mir'', Italian ''mi piace''). However, the original ''Ĉi tiu plaĉas al mi'' continues to be commonly used.

For later changes to the language, see [[Modern evolution of Esperanto]].