A brief July 26 Time magazine article by Olivia B. Waxman (link) addresses the historical context of Esperanto, and it’s noteworthy for being relatively accurate. For example, she points out that while Esperanto was initially an “invented” language, it quite soon started evolving naturally in use. I’ve heard so much nonsense about Esperanto I was delighted to see something fact-based for a change.
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The distinction between natural and artificial language is more apparent than real. My own experience after many decades of using Esperanto is that a planned language can be “internalised” as well as any mother tongue.
I agree. For one thing, there is a continuum of “artificiality.” While speakers of English can be forgiven for not realizing it, many modern natural languages are the result of varying degrees of planning.
Israeli Hebrew, for example, is derived from classical versions of the language (biblical, rabbinic, and so on), but Mendele Mocher Sfarim, Eliezar ben-Yehuda, and others in the late 19th and early 20th centuries introduced thousands of new words, standardized the pronunciation, and even slightly altered the grammar. Icelandic is governed by an academy that has remarkably enough even succeeded in driving out some established loan words from other languages. The geographical concentration of the primary speaking population is probably what makes this practical. Esperanto, with a language community scattered across continents, has developed far less artificially than has Icelandic.
What a lot of people think they know about Esperanto is based on a combination of rumor and naive assumptions about its supposed artificiality.