I know what happiness is, for I have done good work.
Anyone can carry his burden, however heavy, until nightfall. Anyone can do his work, however hard, for one day. Anyone can live sweetly, patiently, lovingly, purely, until the sun goes down. And this is all that life really means.
Don't ever confuse motion with progress.
Perpetual devotion to what a man calls his business is only to be sustained by perpetual neglect of many other things.
If a man loves the labour of his trade, apart from any question of success or fame, the gods have called him.