Tweet [1]
… is from Lord Acton’s letter of March 15, 1880, (available free-of-charge here [2]) to Mary Gladstone:
Ideas have a radiation and development, an ancestry and posterity of their own, in which men play the part of godfathers and godmothers more than that of legitimate parents. We understand the work and place of Pascal, or Newton, or Montesquieu, or Adam Smith, when we have measured the gap between the state of astronomy, of political economy, etc., before they came and after they were gone.