Hmmm, I don't know if all of this really suggests that
We don't think a language can be worth learning if it is simple. It seems that the complexities of various languages reflect more the organic nature of language than any sort of conspiracy by language users.
The linguist
Steven Pinker points out, for example, that irregular verbs can often be explained in terms of
phonology: generating inflected verbs by our language's regular rules could produce words we'd find too difficult to pronounce, whereas "Irregulars ... all have standard Anglo-Saxon word sounds such as grew and strode and clung, which please the ear and roll off the tongue." (p.19).
The ability to pronounce a word obviously falls outside of our language-psychology.
It is also interesting to note that across various languages the irregulars tend to name the same concepts ("be, have, do, go, and say") (p.18)! Pinker points out that any irregularities in the naming of these concepts (which might, for example, stem from the diverse origins of the language) are more likely to be retained because of their frequent use.
Were we to suddenly adopt an
artificial language such as
Esperanto, a number of irregularities would come into parlance after a few generations. This is not because we love inconsistency. Rather, these inconsistencies are actually less obviously advantages to breaking the rules that emerged as the language was thrown back and forth (there was definitely never a single user of our language who suddenly decided "hey, it’s a lot easier to say grew than growed!").
The genetics of languages - the origin of a particular aspect of a language in an older language - could also account for many of inconsistencies in a language as a whole. This is certainly how we should think about the complexities of Japanese
orthography that thbz discusses. I'm sure native and foreign speakers of Japanese would prefer a simpler system for writing their language, but that's just not the way their language evolved.
In summary, the complexities of languages take form in an unconscious way - through an organic process of trial and error that reflects more than what individuals enjoy about using their language.
Both quotes are from "Words and Rules: The Ingredients of Language" by Steven Pinker.
Thanks to Albert Herring, for pointing out an error in the first version of this write up.