Sometimes war is necessary to teach us the value of peace. Sometimes you need to learn the real value of diplomacy in avoiding war. And I'd rather my students learned those lessons on the playground than on the battlefield.

Meaning: Your own mistakes can teach caution, but another person’s experience may offer the same lesson without the same cost. Listen for relevant lessons before repeating an avoidable error.

Meaning: A settlement may avoid the expense and strain of a prolonged dispute. The proverb favours agreement where it is fair and workable, without making cost a reason to abandon protection, accountability or a legitimate claim.

Meaning: People who act from anger may find that trouble follows. Want here concerns lacking trouble, so the saying warns that angry reactions can supply plenty of it without making the emotion itself a moral failure.