Mine is shared, so I hope to get my name on it along with those of a bunch of relatives (hopefully, the names already on it will include my mother but will not include my nephews - Bros names optional). Make room, coming in!*
There are a couple of names on it where the body didn’t end up there; the grave acts both as a temporary deposit for rotting bodies and as a memorial for any family members who died, including those who chose to donate the body.
He used the quote in one of his books but he didn’t invent it. It’s an old Asian proverb (it’s best known in its Japanese form but it apparently originated in China).