Just do what must be done. This may not be happiness, but it is greatness.
A life spent making mistakes is not only more honourable, but more useful than a life spent doing nothing.
Beauty is all very well at first sight; but who ever looks at it when it has been in the house three days?
Progress is impossible without change, and those who cannot change their minds cannot change anything.
Success does not consist in never making mistakes but in never making the same one a second time.