Only "Happy Birthday to you" is sung more often than Scotland’s hymn of conviviality. It is possibly the most-sung song by most people in musical history, a veritable anthem for the world.  Yet, of all these millions who sing it annually, only a few know the original (or even correct) words, and even fewer understand what they mean.  Generations of errors have been incorporated into the original lyric; it may take another millennium to get rid of them.