Robots are the subject. I have a Chinese version of this monster and it is protective. It has fall sensors from the bottom for the case of the multi-storey of your home and this leads to a situation that would please Nietzsche himself. I don't have a staircase, but there is a carpet in the hall with small areas of black (well, the color is like that). He runs on them, stops intentionally and begins to scream that he will not move from his place because he sees an abyss under him. He, a small round piece of plastic and iron, looks at such a banal thing as a carpet and sees there Great Nothing. Technical support advised to glue the sensors to be white and he is joyfully chasing the carpet. But I know that I blinded him and deprived him of something existentially important.