From a Letter to His Daughter By Ralph Waldo Emerson

Finish each day and be done with it.
You have done what you could.
Some blunders and absurdities
no doubt have crept in;
forget them as soon as you can.
Tomorrow is a new day;
begin it well and serenely
and with too high a spirit
to be cumbered with
your old nonsense.

This day is all that is
good and fair.
It is too dear,
with its hopes and invitations
to waste a moment on yesterdays.