Is there a language that is most difficult to learn?

Encyclopedia of Opinion

Question: Is there a language that is most difficult to learn?
Position1 of 2›: No, all languages are complex, and linguistic complexity is relative
Argument‹2 of 2: All languages are equally complex

The Equal Complexity Hypothesis proposes that all languages are equally complex in their own way--whether in phonetics (pronunciation) or syntax (grammar). A language can be simpler in one factor but is complex in another.

The argument

All languages are complex in their own way. By surveying and studying the phonetic, syntactic, morphological, organizational factors of languages, one can observe that languages are complex in their own way. One language may have fewer possible consonants, which causes it to have much longer words, while another language may have over 1200 possible consonants due to its possible tones and sounds, giving it words with fewer syllables. For example, Mandarin Chinese has a relatively simple grammar that lacks plural markings or verb tenses, but it also has complex pronunciation due to its four tones. (Complex, at least, from the point of view of non-tonal languages like English and Spanish. Around 70% of the world's languages are tonal.) Even if linguists find a way to objectively measure linguistic complexity, they must take such measurements from one language’s point of view. Linguistic complexity may include many more forms of meaning, such as whistles or songs that a linguist may misunderstand because they come from a certain linguistic point of view. Since there are several unknown factors to measuring linguistic complexity, it is better to assume all languages are complex and uniquely structured in their own way, just as all humans and cultures are unique.

Premises

[P1]Surveying languages' phonetic, syntactic, and morphological factors shows each is complex in its own way — Mandarin has simple grammar but complex tonal pronunciation. [P2] A trade-off in one area, like fewer consonants, is offset by complexity elsewhere, like longer words. [P3] Any measure of complexity is taken from one language's point of view and may miss forms like whistles or songs. [C] Therefore, because all languages are equally complex and complexity is relative, there is no single most difficult language to learn.

Counter-arguments

Linguists have mostly debunked The Equal Complexity Hypothesis with computational, quantifiable approaches to measuring complexity that came about in the 1990s. Nevertheless, linguists do not agree on a method to objectively measure linguistic complexity. Linguists do not agree on how to define “complexity,” and methodologies to measure complexity are inconsistent across studies.

Rejecting the premises

[Rejecting P1] The Mandarin example illustrates a trade-off; it does not measure one. Observing that a language is simpler in morphology and more demanding in phonology shows that complexity is distributed differently across domains, not that the totals come out equal — which is the premise's actual claim, and the one that would require a metric. [Rejecting P2] Compensation is asserted as a general law on the strength of a few illustrations, and it is precisely what the recent literature has put in doubt. Quantitative work since the 1990s has reported languages that appear more complex than others across several domains at once, and creoles are widely, though not universally, analysed as morphologically simpler than their source languages. [Rejecting P3] This premise undercuts the equality claim as much as the inequality one. If complexity cannot be measured neutrally, then equality has not been established either, yet the position's title asserts exactly such a comparison. The conclusion also changes the subject: difficulty of learning is relative to the learner's first language, and institutions that train language learners routinely estimate it from the hours their students require — a practical measure entirely compatible with every language being complex in absolute terms.