Since English descends from Proto-Germanic, which descends from PIE, would either of those two languages be relatively easy to learn (compared to, say, Japanese), or has the language changed too much to be learnable? Certainly people are able to learn Latin, especially those native speakers of Romance languages and English, so would they have much difficulty with Proto-Italic?
3Good question. I sometimes wonder the opposite: if someone (coming from whatever language background) learns a certain proto-language, would it become a lot easier to learn its modern descendants?– Otavio MacedoAug 7, 2012 at 3:26
That's a very good point as well. I think that would be useful for learning a lot of languages. If you want to learn a family, learn the proto, then the descendants.– Nick AndereggAug 7, 2012 at 11:15
2@NickAnderegg: if an anglophone wanted to try and learn Spanish, I certainly wouldn't advise him to learn Latin first...– JPPAug 14, 2012 at 12:48
This is subjective, but take into consideration the following points.
PIE was a quite complicated language with multiple cases and rich inflections. It had more complicated morphology than English, but compared to Latin, German or Russian it does not look too exceptional.
Much of PIE vocabulary is quite well preserved in Latin and Greek so for a person familiar with modern European languages many roots and stems will be easily recognizable.