Maturity - among other things, the unclouded happiness of the child at play, who takes it for granted that he is at one with his play-mates.

This line is associated with Dag Hammarskjöld’s private spiritual and philosophical reflections, written for himself rather than for publication, and later issued posthumously as *Markings* (*Vägmärken*). In these notebook-like entries—composed during his years as a Swedish civil servant and, later, while serving as Secretary-General of the United Nations—Hammarskjöld repeatedly returns to the theme of inner growth: how a person becomes more whole, more truthful, and more capable of community. The remark frames “maturity” not as sophistication or hardness, but as a recovered simplicity: a state in which one’s relation to others is unforced and unselfconscious, like children absorbed in play.

Hammarskjöld links “maturity” not to sophistication or detachment but to a recovered simplicity: the child’s absorbed play, free of self-consciousness and suspicion. The child “takes it for granted” that he belongs with others; the unity with playmates is assumed rather than negotiated. Read this way, maturity includes an inner clarity—“unclouded happiness”—that comes from trust, presence, and a lack of ego-driven separation. The line also reflects Hammarskjöld’s recurring spiritual-ethical concern with overcoming isolation: genuine adulthood is compatible with innocence, and real community begins when one no longer needs constant proof of acceptance.