[Here is] advice from Rabbi Simcha Bunam, a Hasidic rabbi who lived in the late eighteenth and early nineteenth century. He told his students that they should keep a note in the right pocket that said for my sake was the world created and in the left pocket a note saying I am but dust and ashes. When feeling down, take out the note from the right pocket. When feeling full of oneself, take out the note from the left.
— Greg Marcus in The Spiritual Practice of Good Actions