A good, real, unrestrained, hearty laugh is a sort of glorified internal massage, performed rapidly and automatically. It manipulates and revitalizes corners and unexplored crannies of the system that are unresponsive to most other exercise methods. – Author unknown, from an editorial in New-York Tribune, quoted in Quotations for

To promote laughter without joining in it greatly heightens the effect. – Honore de Balzac