Final answer:
A bad joke can still make people laugh because humor is subjective.
Step-by-step explanation:
The paradox about the "chestnut" or bad joke is that it is bad, yet it still makes people laugh. Even though the joke may be old and widely known, it continues to elicit laughter from those who hear it. This is because humor is subjective, and what may be considered a bad joke by one person may still be amusing to others. It is important to note that a bad joke can still have comedic value and be appreciated for its traditional or classic nature.