Lit. Secret Principles on the Way of Painting, a late 17th-century discourse on painting *garon 画論 dictated by Kano Yasunobu 狩野安信 (1613-85) to his disciple Shōun 昌運 (1637-1702), presenting the fundamental principles of the Kano school *Kano-ha 狩野派. Written in 1680, Gadō yōketsu is divided into eighteen sections and an introduction. Intended as a secret manual, the book was given as a graduation certificate to Kano students who had mastered its principles and techniques. Yasunobu makes extensive use of Chinese texts, attempting to ground the Kano school style in the theoretical writing of Chinese masters. Along with technical instructions, Yasunobu discusses the Kano approach to painting. According to the theory of talent and training, artists are separated into those with natural skill and those whose skill derives from training and the study of manuals containing the teachings of past masters. Yasunobu favors the later type of artist because their works are impersonal and thus timeless, while the skills of creative artists die out with them.
A brief survey of the eighteen chapters reveals the basic function and ideology of the work:
- The Six Laws based on Zhang Yenyuan's (Jp: Chō Gen'en 張彦遠, fl. mid-9th century) Lidai minghuaji (Jp: Rekidai meigaki 歴代名画記; Record of Famous Painters), focusing on the creation of spirit through refinement of the brush and selflessness.
- The artist must harmonize the spirit of his painting with the spirit of nature by first harmonizing his own spirit with that of nature.
- The cosmic forces do not need to borrow artificial colors—Chinese ink contains the five colors which express the myriad changes of the four seasons.
- When drawing circles and straight lines, strokes should not be too quick nor too slow, too thick nor too thin.
- The study of the painting of Gu Kaizhi (Jp: Ko Gaishi 顧愷之), a 5th-century Chinese painter who specialized in portraits and figure paintings.
- A discussion of the Three Classes *sanpin 三品 based on Lidai minghuaji and Jing Hao's (Jp: Kei Kō 荊浩 fl. ca. 870-930) Bifaji (Jp: Hippōki 筆法記; Laws of the Brush).
- The Six Laws rikuyō 六要 from Xie He's (Jp: Sha Kaku 謝赫, fl. late 5th-early 6th century) Guhua pinlu (Jp: Koga hinroku 古画品録; Classification of Painters).
- The Six Essentials from Bifaji and Han Zhuo's (Jp: Kan Setsu 韓拙, fl. ca. 1095-1125) Shanshui chunquanji (Jp: Sansui junzenshū 山水純全集; Chunquan's Compilation on Landscape).
- The Three Illnesses sanbyō 三病 from Shanshui chunquanji, Bifaji, and Guo Ruoxu's (Jp: Kaku Jakkyo 郭若虚, fl. ca. 1070) Tuhua jianwenzhi (Jp: Toga kenmonshi 図画見聞誌; Experiences in Painting).
- The theory that without assiduous attention to likeness in color of fine detail, superior artist can produce a sense of naturalness.
- That one should paint with peace of mind, fresh spirit, freedom of movement, proper rules and sufficient tools.
- A description of how to paint Buddhist images
- And how to paint followers of the way, dōin 道人 or Taoists.
- Instructions on painting holy men hijiri 聖 or Buddhist saints
- Landscape
- Scenery of the four seasons
- The painting of Wu Dazoi (Jp: Go Dōshi 呉道子), an 8th-century Chinese master of brushwork
- The landscape paintings of 11th-century Chinese painter Yen Su (Jp: En Shuku 燕粛).