The songs I had are withered Or vanished clean. Yet there are bright tracks Where I have been.

-Gurney, Ivor
  'The Songs I Had'.

   For what has beenöthanks! For what shall beöyes!

-Hammarskjo«  ld, Dag HjalmarAgne Carl
  Va«  gmarken (translated by L Sjsy«  berg and W H  Auden as Markings,1964).

If, of all words of tongue and pen, The saddest are,'It might have been,' More sad are these we daily see: 'It is, but hadn't ought to be.'

-Harte, (Francis) Bret
  'Mrs.  Judge  Jenkins'.

Dost thou look back on what hath been, As some divinely gifted man, Whose life in low estate began And on a simple village green; Who breaks his birth's invidious bar, And grasps the skirts of happy chance, And breasts the blows of circumstance, And grapples with his evil star.

-Tennyson
  In Memoriam A.H.H., canto 64, l.1^8.

For of all sad words of tongue or pen, The saddest are these: 'It might have been!'

-Whittier,John Greenleaf
  'Maud Muller', l.105^6.