According to the writer, a person is like "a child who just stands alone on the street of life" after being lost, disappointed and rattled. So there is no "adult". The "adult" is nothing but the terminal form of a "lost child" after playing around himself with "stupidity, oblivion and doctrines" without knowing that he made a mistake. From essays, "Grasp Sand And Stand Up."
"May 11 2019
from “Oriori no Kotoba” by Kiyokazu Washida, The Asahi Shimbun"