Eighteenth-century Scottish poet Robert Burns wrote or adapted one of the most instantly recognizable songs in the world, "Auld Lang Syne," which is chorused annually around the globe on New Year's Eve or at the end of any pleasant evening or convocation. Yet, like the poet himself, these lines--written in the Scots dialect--are rarely understood. The most famous chorus in the world, "For auld lang syne, my jo, / For auld lang syne, / We'll tak a cup o kindness yet, / For auld lang syne," is parroted by singers who feel the sentiment of the lyrics but do not understand their exact meaning. "For the old long ago" is the literal meaning; other translations include "For days gone by" and "For the old times." Much the same difficulty confronts the non-Scots reader of the some 650 poems and songs Burns created during his mere thirty-seven years of life. Written in Scots...