Technically by choosing OLD AGE, he condemned himself to a life long sentence. Now there is a discussion about life long sentences in prison, as the Netherlands is the only EU country where life long sentence actually means you are behind bars until you die and getting parole is possible, but requires a royal decree, which is almost never given. Some people serving a life long sentence have stated that being executed (which is by article 114 of the Dutch constitution not possible) would be more humane.
Well, that is all philosophical, the riddle and the joke behind it was a good one.