Because a thing is difficult for you, do not therefore suppose it to be beyond mortal power. On the contrary, if anything is possible and proper for man to do, assume that it must fall within your own capacity.
Marcus AureliusWhen force of circumstance upsets your equanimity lose no time in recovering your self-control, and do not remain out of tune longer than you can help. Habitual recurrence to the harmony will increase your mastery of it.
Marcus Aurelius