“Observation performed merely on its own is no more than what a machine can do—a surveillance camera, for instance. And imagination on its own, practiced by itself for too long, can cut you off from the world. You might wander away, like a hermit to a cave, becoming only a spirit to the rest of humanity. However, if you remain in the world, and you train yourself to combine observation and imagination in proper proportion...then you may change the world itself.”