It is said that Shozo Shimamoto came up with the group name "Gutai" while the members were coming up with their own ideas. Sadamasa Motonaga said in a lecture about the meaning of the name "Gutai" as follows:
"Some people mistook the word "Gutai" for a figurative painting. Let's say a painting of an apple, for example, no matter how realistically it is drawn. Even if the painting is realistic, you cannot eat the apple. All these things are illusions and are called illusionism.
Paint is chemicals, oils, minerals, etc., and canvas is cloth and wood. We are thinking about what we can do with these materials. That is the concrete.
These words are a simple explanation of what Jiro Yoshihara declared in his "Gutai Art Manifesto" published in Geijutsu Shincho in 1956.
“Gutai art does not transform matter. Gutai art gives life to matter. Gutai art does not falsify matter. In Gutai art, the human spirit and matter remain in conflict and shake hands. ...When matter exposes its characteristics as it is, it begins to tell a story and even screams."
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The concept of concretization is not to create art in order to reproduce some model or motif, but to challenge to reconstruct the beauty and uniqueness of the material itself in a new form.
Gutai member Tsuyoshi Maekawa contributed the following text to the solo exhibition held at the Karuizawa New Art Museum in 2020.
"In my more than 60 years of production, I have been obsessed with materials, and among them, I may have been obsessed with "cloth" from beginning to end. My most important beliefs when creating my work are that it should be unique, not imitative, not derivative, not literary or religious, etc., and that it should be purely abstract in color, form, and substance."
It was this kind of thinking on the part of all the members that made it possible for Gutai to maintain a high level of artistry. The word for matter itself is concreteness, which connects to the purpose of Gutai.