While playing this game, use the rules as guidelines to tell the stories you wish to tell and have fun. They are there to provide a dramatic backdrop and sense of mechanical balance. You are not only encouraged but expected to create your own rules, play fast and loose with the rules when appropriate, and make allowances for good storytelling when it conflicts with the rules. If you are not having fun, change something to make it so you are.
Furthermore, we not only encourage but expect and assume that you will take the rules into your hands, modify them, and add new material for your game.
This game is largely governed by the consensus of those who play the game. This game has cooperative storytelling elements at its core.
This is not a “design philosophy” - this is a codified and expected part of play. It is our mechanical intention that this be honored as much as things like “AC” and “HP”.