You can do something and have no recollection that you did it. A scary thought.
I had a library book that was due. I searched for it in order to return it before the due date, couldn’t find it, and thought I lost it. When Mike checked my library account, it showed that it was returned! I checked at the library and there it was, on the shelf.
I must have returned it, no one else would have. But I don’t remember doing it! I could imagine myself driving by, and dropping it off in the book drop, but I can’t remember that I actually did. If I imagine it enough times, I could convince myself that I actually did it. But how would I know if I did return the book, or I created a memory to say that I did?
What else did I do and not remember, or have a memory of doing something but did not actually do it?
It’s a fine line between imagination and reality.