"In the life of every man there are sudden transitions of feeling, which seem almost miraculous. At once, as if some magician had touched the heavens and the earth, the dark clouds melt into the air, the wind falls, and serenity succeeds the storm. The causes which produce these changes may have been long at work within us, but the changes themselves are instantaneous, and apparently without sufficient cause."

Source: Oliver Wendell Holmes, Nathaniel Hawthorne, James Russell Lowell, John Greenleaf Whittier, Henry Wadsworth Longfellow (1850). “The Boston book: being specimens of metropolitan literature”, p.362