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• We live, but a world has passed away
  With the years that perished to make us men.
  • The Mulberries (1871)

• Lord, for the erring thought
  Not into evil wrought:
  Lord, for the wicked will
  Betrayed and baffled still:
  For the heart from itself kept,
  Our thanksgiving accept.
  • A Thanksgiving

• And before you know me gone
  Eternity and I are one.
  • Time

• Her mouth is a honey-blossom,
  No doubt, as the poet sings;
  But within her lips, the petals,
  Lurks a cruel bee that stings.
  • The Sarcastic Fair

• He who sleeps in continual noise is wakened by silence.
  • Pordenone, IV

• See how today's achievement is only tomorrow's confusion;
  See how possession always cheapens the thing that was precious.
  • Pordenone, IV

• The wrecks of slavery are fast growing a fungus crop of sentiment.
  • Their Wedding Journey (1872)

• The mortality of all inanimate things is terrible to me, but that of books most of all.
  • Letter to Charles Eliot Norton (April 6, 1903)

• I am not sorry for having wrought in common, crude material so much; that is the right American stuff; and perhaps hereafter, when my din is done, if anyone is curious to know what that noise was, it will be found to have proceeded from a small insect which was scraping about on the surface of our life and trying to get into its meaning for the sake of the other insects larger or smaller. That is, such has been my unconscious work; consciously, I was always, as I still am, trying to fashion a piece of literature out of the life next at hand.
  • Letter to Charles Eliot Norton (April 26, 1903)

• Clemens was sole, incomparable, the Lincoln of our literature.
  • My Mark Twain (1910)

Unsourced

• Some people can stay longer in an hour than others can in a week.

• The action is best that secures the greatest happiness for the greatest number.

• The secret of the man who is universally interesting is that he is universally interested.

• There will presently be no room in the world for things; it will be filled up with the advertisements of things.