Prince: Writing Memoirs ... He Seemed to Know Death Was Coming

There's evidence Prince's death was not unexpected, because we've learned the superstar started writing his memoirs just a month ago.

Sources connected with Prince tell us, they were surprised he started the project ... something he had been mulling over for years but not acting upon. We're told he had finished around 50 pages at the time of his death.

What's more ... last Saturday night, after Prince was admitted to a hospital for what his reps called the flu, he addressed a crowd at Paisley Park near his home and said, "Wait a few days before you waste any prayers."

Whatever was ailing Prince, it was serious enough to sideline him several weeks ago from doing 2 shows, and it clearly lingered because he had to make an emergency landing last Friday, just 48 minutes from his home.

Our sources say Prince was upset the news got out that he had been hospitalized, and feared people would think he was already dead.