Earlier quoted context omitted.
There’s no excuse for not knowing at least three out of English, Spanish, French, Mandarin, Urdu, Arabic, Portuguese, Russian and German. If you’ve finished university peeking at a fourth and fifth language can’t hurt either. How many do you know? Edit: Oh, and how about a bit of Latin and Greek, maybe?
I do know English, Spanish and Italian and I'm doing my best learning Portuguese but that doesn't mean we should encourage a world divided by language barriers. I'd be happy to completely forget about every language, including my own native language, and having English as a universal language, it's called progress. There's no advantage whatsoever in having a fragmented world, and if the mess in my head is any indicat…
After all, knowing more than one language does give you some different insights, not just into the culture of the other language but also into your own culture. Furthermore, there is a whole canon of classical works in basically every language which would likely lose some of its value if it were only accessible in the translated form.
We can add to the last point by taking note that English is a particularly bad example of a ‘world-wide native language’. While its simplicity – both with regards to its vocabulary and its grammar – certainly helps when it is the second language of someone, such concerns are of smaller importance when you want it to be everyone’s first language: Such a language can come with a much stronger set of grammatical rules and nicer ways to build composite words and still be (roughly) equally accessible to its native speakers.