Recognition is the quality that permits gratitude to be transformational. To recognize is to cognize, or think, differently about something from the way we had thought about it before. Think about an experience in your life when what was initially a curse wound up being a blessing in disguise. . . . Gradually, you emerged from the resulting darkness with a new perception. Adversity was transformed into opportunity. Sorrow was transformed into gratefulness. You re-cognized the event.
— Robert A. Emmons, Thanks! How the New Science of Gratitude Can Make You Happier