Emeka is preparing a speech for his school's debate competition. He has done the research. He has twelve strong points. He practises all twelve and feels confident. He loses. After the event, a judge gives him feedback: with twelve arguments, I could not remember any of them. This is exactly the problem that the first principle of Made to Stick is designed to solve. Simple does not mean short. It does not mean easy. It means finding the single most important thing — the core — and letting it drive everything else. The Heaths' favourite example of simplicity in action comes from the US Army. Military planning involves thousands of detailed instructions. But commanders discovered a problem: no plan survives contact with the enemy. The environment changes too fast. Soldiers cannot wait for instructions. They need to know enough to make good decisions on their own. The solution was Commander's Intent. Every military order now begins with a single, plain-language statement of the goal — not the steps, but the destination. If we accomplish nothing else tomorrow, we must achieve this. As long as every soldier knows the intent, they can improvise and adapt without losing direction. Southwest Airlines runs on the same principle. Their CEO Herb Kelleher once explained: I can teach you the secret to running this airline in thirty seconds. We are THE low-fare airline. Once you understand that, you can make any decision in this company as well as I can. That phrase — THE low-fare airline — is Southwest's Commander's Intent. When a marketing manager proposes adding chicken salads to flights, the answer is immediate: will that make us THE low-fare airline? If not, the idea is gone. John F. Kennedy understood this too. When he announced the moon mission in 1961, he could have said: our mission is to become the international leader in the space industry through maximum team-centred innovation and targeted aerospace initiatives. Instead he said: put a man on the moon and return him safely by the end of the decade. Simple. Unexpected. Concrete. A single sentence that focused the effort of an entire nation for a decade. The Heaths' instruction: stop asking what else you can add. Start asking what you can take away. The core is what is left when everything non-essential has been removed.