Because we know the rules. We know the world we’re operating in. We know our own capabilities. We know there is randomness, provided by the dice. And we know that the people we’re playing with know all that too.
Within that framework, each one of us can play freely with the skills we’re given and the attributes we acquire. We can collaborate, go it alone, or switch between the two. If we’re Dungeon Master, we can even change the rules.
Nothing is predetermined, there’s room for the unexpected, yet everything is coherent. It’s a safe space enclosing the perfect balance between constraint and freedom, between box and creativity, between process and play, between community and individual.