I've seen many write-ups about a universal language world-wide.  Esparanto is at the top of the list, but there are two that go back hundreds, if not thousands of years (IMHO).

First is mathematics.  No matter what language you speak primarily, the formulas never change.  Ergo, you can communicate by number regardless of how linguistically clumsy you may be.  Like I've heard time-and-again...I challenge your argument and I can prove it mathematically!

The secound would be music.  If you've ever looked at sheet music, you can see that regardless of how phrases are written the notes still fall on the same lines on the scales.  Although it may be a bit awkward trying to convert musical notes into words, two people can communicate in basic form through chords, rhondos and other styles.  Think of the song 'Dueling Banjos'.

Your opinion?