Plato warned against the dangers of humor because he wanted to protect the guardians of the republic from the distortions and distractions of laughter.

Plato believed that humor had the potential to undermine the serious and focused mindset that he believed was necessary for the guardians of the republic to maintain. He felt that laughter could lead to a loss of control and a disregard for disciplinary norms, which could ultimately harm the stability and integrity of the state. For this reason, he believed that only limited and carefully selected forms of humor should be allowed in society.