The most important character in these stories is of course Isaac, and his experiences as a young boy provide the main theme. But other characters play significant roles as well, including the rest of the Singer family, Isaac's friends, and the people he meets. One of Isaac's best friends is Boruch-Dovid, who takes him on an adventure into the outlying countryside around Warsaw to see the "wild cows." The day fills Isaac with delight, mostly from the wonderful sights of nature denied city dwellers. In addition, Isaac learns that the wild cows exist only as figments of Boruch-Dovid's imagination, which Isaac comes to appreciate. In "The Strong Ones," Isaac has a temporary falling out with his friend Mendel for reasons he at first does not understand, but eventually the two make up. "The Mysteries of the Cabala" demonstrates Isaac and Mendel's shared passion for...