Marusankakushikaku, also known as The Universe in English and as ○△□ referencing the work, is a zenga by Sengai, speculated to be made between 1819 and 1828.

The artwork consists of three shapes, "○" (circle), "△" (triangle), "□" (square), drawn with ink.

[2][3][4] On the left of the work, the rakkan [ja] (sign and seal) of Sengai and the phrase Fusō saisho zenkutsu (扶桑最初禅窟) are written.

However, it is speculated that the shapes were drawn from the left due to the darkness of the ink, which raised concerns whether the work should be called "○△□" due to some people wanting to call the work "□△○" to respect the order of shapes.

Suzuki said that the work is the universe drawn by Sengai, and the circle stands for "infinite", the triangle for "the start of all things", and the square for two triangles, meaning that the process continues indefinitely, resulting in countless events.