When I was younger my memory was rock solid in that if I recalled something it was 100% true. As I got older my memory is not as certain, but at least I know my memory is not always correct.
The loss of the reliability of my memory is probably the thing I most about my youth.
"When I was a boy of fourteen, my father was so ignorant I could hardly stand to have the old man around. But when I got to be twenty-one, I was astonished at how much he had learned in seven years."
Yes an interesting question. I do have written evidence from the time, but I also have a whole lot of independent memories of having a rock solid memory. I don’t seem to have false memories, just incomplete memories.
It is not like my memory is bad now (it is still better than nearly everyone I know), it just is not as good as it used to be. I have to write things now in my diary and use bookmarks when I read, rather than just remember which page I was up to.
The loss of the reliability of my memory is probably the thing I most about my youth.