Zeami's collected theoretical writings, along with those of his son-in-law Komparu Zenchiku, form the primary corpus of nogakuron. Zeami's early treatises are driven by a tension between two contrasting ideals, yugen and monomane. The most prominent aesthetic ideal in Zeami's writings is hana, the Flower. Zeami is famous for his extensive treatment of jo-ha-kyu. Zeami wrote only one treatise on the art of playwriting, The Three Paths. For woman plays, the ideal protagonist roles are Heian court ladies. In an early treatise, Kabu zuinoki, Zenchiku reveals his deep fascination with waka. Zenchiku is best known for his original theoretical construct rokurin ichiro. The treatises of Zeami and Zenchiku provide invaluable insight into the formative years of noh drama. Zeami constantly strives to adjust his art to a level of refinement suitable for his audience. This is evidence of a medieval concern with the process of reception, with affective theory, due to the social nature of the era's dominant literary arts.