Tōhaku's Explanation of Painting, comments of the Momoyama period painter Hasegawa Tōhaku 長谷川等伯 (1539-1610) on well-known Chinese and Japanese painters, paintings and techniques. It is known as the first essay by a painter in Japan. The inscription says that around 1592 priest Nittsū 日通 of Honpōji 本法寺, Kyoto, recorded Tōhaku's statements on painting, and later they were compiled randomly in a small bound book. The original text is still owned by Honpōji. Although the book is commonly known as Tōhaku gasetsu, the original title reads "Comments on Painting: Record of what Hasegawa Tōhaku Told" Ga no setsu: Hasegawa Tōhaku monogatari kore-wo kisu 画之説:長谷川等伯物語記之.
The work discusses nearly 50 Chinese and Japanese painters including Liang Kai (Jp: Ryōkai 梁楷, act. early 13th century), Muqi (Jp: Mokkei 牧谿, act. late 13th century), Yujian (Jp: Gyokkan 玉澗, act. late 13th century; see *sōgenga 宋元画), as well as Mokuan 黙庵 (died in China ca. 1345), Nōami 能阿弥 (1397-1471) and Sōami 相阿弥 (?-1525; see *Ami-ha 阿弥派). In particular Tōhaku paid special attention to the lineage of Josetsu 如拙 (act. early 15th century), Shūbun 周文 (act. first half of 15th century), and Sesshū 雪舟 (1420-1506) and his followers, the lineage into which Tōhaku placed himself. The text is translated into English by Michael Cunningham in the appendix to his unpublished dissertation "Unkoku Tōgan 雲谷等顔" (University of Chicago).