In the whole round of human affairs little is so fatal to peace as misunderstanding.

Sangster’s aphorism treats “misunderstanding” not as a minor social mishap but as a primary engine of conflict. By calling it “fatal to peace,” she suggests that harmony in families, friendships, workplaces, and public life depends less on perfect agreement than on accurate comprehension—of motives, words, and circumstances. The line implies that many quarrels arise from misread intentions, incomplete information, or careless communication, and that peace is therefore an active achievement: it requires patience, clarification, and charitable interpretation. The breadth of “the whole round of human affairs” universalizes the warning, making it applicable from intimate relationships to civic and international disputes.