Ship captain is in charge of keeping ship’s log.
He notes “NE wind, calm sea, today first mate is drunk.”
After seeing that first mate asks captain to remove the note about him as it would harm his career.
“No, I can’t do that” declines the captain
“we only write the truth in the log.” Seeing there is nothing he can do first mate drops the issue.
Next day it’s his turn to keep the log and he writes “N wind, calm sea, today the captain is sober.”