Have you ever noticed that what is exciting on Monday tends to become boring on Friday? Even passionate relationships, stimulating jobs, and breathtaking works of art lose their sparkle after a while. As easy as it is to stop noticing what is most wonderful in our lives, it’s also possible to stop noticing what is terrible. People get used to dirty air. They become unconcerned by their own misconduct, blind to inequality, and are more liable to believe misinformation than ever before.