Catching a catfish with a gourd (瓢鮎図, Hyō-nen-zu) is a hanging scroll painting by the 15th-century artist Josetsu (如拙). The painting was executed in c. 1415 and is held by Taizō-in, a sub-temple of the Myōshin-ji complex of Zen Buddhist temples in Kyoto. It is one of the earliest suiboku (ink wash) paintings in Japan and was designated as a National Treasure of Japan in 1951. The painting is accompanied by many inscriptions, and may be considered an example of shigajiku (a “poem-and-painting scroll”).
https://en.wikipedia.org/wiki/Catching_a_catfish_with_a_gourd
Maybe a dumb question, but I can’t recognize if the person has a human head or a rat-like one?
Human. He’s just pudgy with unkempt hair and a beard. Here’s a different scan of the same piece - it’s black and white but less artefacted.
Actually looks like he is a catfish catching a cat fish. Maybe along the lines of you are what you eat?