Final answer:
Morreall believes that philosophers and stand-up comedians share a belief that relaxation through humor is essential to health.
Step-by-step explanation:
According to Morreall, philosophers and stand-up comedians share the characteristic of having a belief that relaxation through humor is essential to health. Both philosophers and comedians recognize the power of humor in providing relief and creating a positive mental state. They both understand that humor can serve as a coping mechanism and can contribute to overall well-being.