Suppose that all the languages in the world have the same number of vocabulary. Is it possible that one language is more superior than another in the way it represents the world, even if they have the same number of words contained in them?

Of course!

To see why, consider a thought experiment: I have heard (and don't know whether it is true or not) that Inuit people have many more words for (the different kinds of) snow than what are available in other languages. But even if this isn't true, one can certainly imagine this sort of thing. So imagine that there is some language spoken by island dwellers whose economy and survival is almost entirely based on hunting/gathering and cultivation of sea life. This culture might have much more sophisticated and complicated descriptions of local sea creatures than ours (organized, in other words, not just in terms of differences in species, but also this combined with sizes, colors, and other traits that may mark off individuals within the species as better for different purposes to which they might be put by the islanders). Briefly, they would have single words for different descriptors that we would have to attempt using many more words to complete the description. In that sense, they might in some way be much better at describing the world locally than we could manage to describe their locality in English. But they might have no words at all for quarks, clocks, or hurricanes (though they might have a word for typhoon). Numerically, they might have the same number of words in their vocabulary, but the net gain in their local ability for accurate description could still be offset by significant incapacities to describe the wold more globally.

Another scenario: suppose that their language is loaded with synonyms--they have four or five words to describe the exact same things. That would unbalance their "economy" of vocabulary in a way that would leave it deficient, relative to other languages with the same number of words, but with fewer synonyms.

I don't see what is so good about brevity in language. What is wrong with lots of synonyms? You then get to choose which word to use. Perhaps it seems that it does not matter, since the choice is between equivalents. Well, they may mean the same thing but they don't sound the same or look the same.

It is worth trying to avoid a Gradgrind theory of semantics!

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