....I totally already know that!
When I'm tired, like I am right now, it's becomes obvious to those around me because I talk in quotes. For some reason my brain ceases to have the ability to come up with it's own original thoughts, but can summon up a pre-recorded thought that fits the situation. It's like having an episode of a usually live show ready to rerun in case something goes wrong with the production. Like I have standby thoughts.
One of my favorite books is "The Mysterious Flame Of Queen Loana" by Umberto Eco. It is about an antiquarian bookseller who suffers memory loss after a car accident, and his memory comes back to him in literary passages and quotes. Books and lines from books jog his memory, and I remember thinking when I read it that if I ever suffered memory loss, mine would trickle back in a similar fashion. And damn, I need to read more.