Whatever our external circumstances, in the end happiness or unhappiness depends on the mind. Consider that the one companion whom we stay with, continually, day and night, is our mind. Would you really want to travel with someone who endlessly complains and tells you how useless you are, how hopeless you are; someone who reminds you of all the awful things that you have done? And yet for many of us, this is how we live—with this difficult-to-please, always-pulling-us-around, tireless critic that is our mind.
Into the Heart of Life, By Jetsunma Tenzin Palmo, page 172