Kafka has a nice fragment in his diaries which editors have posthumously published as a parable entitled Katz und Maus/Cat and Mouse. In it a mouse is running. The world always used to be so wide, he thinks to himself. But now it is getting narrower and narrower. He finds himself running into a oorner with nowhere to go. Enter the cat. The cat says, all you need to do is run the other way and gobbles him up.
A maths teacher loved the wide world of numbers. They stretch out to infinity. They are so pure and unsullied by the world. But now the maths teacher is running. He needs to find his place in the world. He finds a job where he must teach children who are not interested in the wide world of numbers. They like the sullied world instead. The maths teacher is in despair. Nobody wants his world of numbers. Enter the shadow. The shadow says, all you need to do is enter the sullied world and find interest there, but the maths teacher is unable to do that and the shadow gobbles him up.