Much of a sustained and successful spirituality hinges upon our memory, on our ability to recall the ways that God has acted in our life. St. Augustine, to take one example, spends a good chunk of the Confessions investigating memory and its relationship to discerning God's activity and will.
But it's not just spirituality that depends upon memory. Our very identity depends, to a remarkable extent, on memory. If we couldn't remember experiences or information, we really couldn't know anything at all. We certainly couldn't know ourselves.
The fascinating subject of memory was taken up recently in the New York Times by professors Christopher F. Chabris and Daniel J. Simons. An excerpt:
When we recall our own memories, we are not extracting a perfect record of our experiences and playing it back verbatim. Most people believe that memory works this way, but it doesn’t. Instead, we are effectively whispering a message from our past to our present, reconstructing it on the fly each time. We get a lot of details right, but when our memories change, we only “hear” the most recent version of the message, and we may assume that what we believe now is what we always believed. Studies find that even our “flashbulb memories” of emotionally charged events can be distorted and inaccurate, but we cling to them with the greatest of confidence.
See the rest of their intriguing piece, "Why Our Memory Fails Us," here.