> "However, if you write about science in English, for example, you can guarantee that 50 years from now your text will feel dated -- just try to read papers from the beginning of the 20th century. On the other hand, we still can read the great works of antiquity (from 20 centuries ago) in Latin."

Starting as somebody exposed to only modern english, getting off the ground with 17th or 18th century english is going to be much easier than getting off the ground with any latin.

Seriously, I'm not sure what english works you have been reading, but it really doesn't get bad until you get really get back into the mid-17th century or so. Even with 16th century stuff, I would say that most of the difficulty comes from antiquated idioms (and rarely vocabulary). Trouble you had with scientific papers from the early 20th century probably had more to do with your inexperience with the subject matter of the paper, not the language it was written in. Books written in the 19th century are still considered reasonable reading for children today (Twain, Carroll, Dickens, Thoreau, etc.)