If there had been no official rulebook, the dispute would have had no honest way of ending. The two captains would each have insisted on their own version; the referee's word could have been challenged as personal opinion; the match might have been stopped, replayed, or awarded by shouting rather than by rule. The team that was stronger, louder or better connected would have won the argument — not the team that was actually right.
What is required for everyone to abide by the rulebook:
- The rules must be written down and public before the match, not invented during it.
- They must be the same for both teams — no special rule for the favourites.
- Everyone must have agreed to them in advance, so that following them is a promise already given.
- There must be a neutral person — the referee — with the authority to apply them.
- The rules must be seen as fair; people obey rules willingly when they believe the rules protect them too.
If the captains refused to refer to the rulebook at all, the game would collapse into a quarrel. There would be no way to decide who won, the tournament could not continue, and future matches would be pointless because no result could be trusted.