Even if you haven't read Don Miguel Ruiz’s first book, The Four Agreements, you know someone who has. Published in 1997, this classic has sold more than eight million copies in the U.S. and has been translated into 46 languages. Don Miguel has steadily written other books since, including Master of Love, The Toltec Art of Life and Death, and The Three Questions, among others. At age 68, the Mexican-born, San Diego-based author has just published The Actor: How to Live an Authentic Life, the first in a mystery school series. The second in the series, The Myth, will come out later this year, as will the third. So what exactly is a mystery school? “Many people say they learn in the school of life, and that’s really what it is,” Don Miguel explains. “It’s life revealing secrets to us.” He’s always been known as a storyteller who uses that form to convey his spiritual wisdom. “Language is how we create ourselves,” he says. In the play “As You Like It,” William Shakespeare wrote that “All the world’s a stage, and all the men and women merely players. They have their exits and their entrances, and …