" My sense of urgency is very simple,' said the professor, 'I've remembered that much. It's because what I have to remember has to do with time running out. And that's what anxiety is, in a lot of people. They know they have to do something, they should be doing something else, not just living hand-to-mouth, putting paint on their faces and decorating their caves and playing nasty tricks on their rivals. No. They have to do something else before they die—and so the mental hospitals are full and the chemists flourishing. "

― Doris Lessing , Briefing for a Descent Into Hell