Several traditional views have dominated the attitude of literary and theatre historians towards eighteenth century English drama. The most influential perspective has been that of Allardyce Nicoll, who lists plays, discovers coherent schools of playwriting, and traces chronology as if it were causality. A second approach looks at the century as a gallery of worthy dramatists, one hanging beside the other: Farquhar, Addison, Steele, Gay, Lillo, Goldsmith, and Sheridan. This approach is exemplified in F.S. Boas's Introduction to Eighteenth Century Drama, an appreciation of the tall peaks which tends to ignore the broad valleys.