Good advice is something a man gives when he is too old to set a bad example.

The quip treats “good advice” less as moral wisdom than as a consolation prize for lost freedom. It suggests that people often become prescriptive only after age, reputation, or diminished opportunity prevents them from indulging in the very vices they now condemn. The line satirizes the gap between preaching and practice, implying that counsel can be motivated by envy, self-justification, or the desire to retain influence when one can no longer lead by action. In the spirit often associated with French moralists, it exposes self-interest beneath respectable language and warns readers to scrutinize the motives behind moral instruction.