The way we habitually think of our surroundings and ourselves create the worlds that each of us inhabit. “There are these two young fish swimming along and they happen to meet an older fish swimming the other way, who nods at them and says ‘Morning, boys. How’s the water?’” the writer David Foster Wallace told a class of graduating college students in 2005. “And the two young fish swim on for a bit, and then eventually one of them looks over at the other and goes ‘What the hell is water?’”

