对Jonathan Blow创作Braid，有两本书不能不提，就是他在访谈中说到的《看不见的城市》和《爱因斯坦之梦》，而且访谈中他也承认游戏中放了不少暗示，等着玩家发掘：

I started out by stylistically imitating Calvino, and I moved away from that as I saw that there were better things for this work. There are a lot of details in the game that I hope that people notice or they at least feel at a subconscious level. There are a lot of things, even in screenshots and stuff on the web, that no one has noticed. I follow forum discussions about the game, and it's cool that nobody's noticing them, because that means that they really are not obvious, and I think once people start discovering those, they'll enjoy the game even more.