Sartwell's Second Law, which states that "a song's excellence is inversely proportional to the square of its distance from the blues." In plain English, the further a band strays from the blues, the worse it is. "Rock is a traditional art form, a popular art form that emerged out of the blues and has to be judged by the standards of blues," Sartwell explains. "If a band tries to make fine art or mistakes itself for Wagner, it has misunderstood the form."