Why it was said

Roger Fisher and William Ury put this at the heart of the chapter that gives principled negotiation its first rule. They had watched negotiators at Harvard's program tangle two different things together: the relationship with the person across the table and the substance of the disagreement. Hard bargainers attacked both; soft bargainers gave way on both. The book's answer was to split them.

What it actually means

Most negotiations go wrong because people treat toughness as a single dial. Turn it up and you damage the relationship while defending your position; turn it down and you protect the relationship by surrendering the substance. Fisher and Ury argue the dial is really two. You can be generous, respectful and genuinely curious toward the person, and at the same time unbending about the merits: the facts, the standards, the interests at stake. Separating them is what lets you hold a firm number without it being an act of hostility, and hear a hard no without it being a personal wound.

How to use it

1. 1Before a difficult conversation, write two lists: what you want for the relationship, and what you want on the substance. Keep them apart in the room.
2. 2When the other side attacks you, answer the problem, not the attack: 'Let's look at what the numbers say.'
3. 3Make concessions to the person freely, such as time, tone and acknowledgement, and none to the problem without something in return.