"The Devil finds work for idle hands": this is the high negative idiom that describes for a long idleness and that hides the doing nothing idea, that in this article we try to discredit; in fact idleness can be considered a moment of great creativity that, even better, opposes to nothing's idea. We can suppose that the "nothing's idea" characterizes not the idleness but the boredom. Or better, a particular type of boredom, invincible and that deprives everything of all meanings and in this way we can define as mental illness.