Just hypothetically. A chain of thoughts. The question isn't unclear. What would you tell your future self in x... Usually it's the way back round. One from t

Just hypothetically. A chain of thoughts. The question isn't unclear. What would you tell your future self in x... Usually it's the way back round. One from the future tells the one from the past not to do something, because the one from the future learned no good of his past's doings. What if that one from the past do not stop in doing that things. Could the one from the future say "Maaa I TOLD YOU SO! So obviously, the knowledge gain is following a linear string in time. There is just a one way'ed "forward". By receiving a not expected letter/email/message, one might be curious what's the letter's content. After reading it, one learns a new whatever the context of the message was. Gain of knowledge. Soo.. by stripping off the writings to logic left: Nothing that I wouldn't remember by myself.