Love Dr Z's reply!
Actually, if it's not inflicting PAIN, then it is not 'sadism' by definition.
It is however a form of shadenfreude (taking amusement in another's humiliation)...or, psychologically, a form of saluromania (deriving pleasure from seeing someone get soiled somehow).
All slapstick humor has some degree of humiliation in its essence, having evolved from the clowning traditions of yore (i.e., August clown = dominant clown who abused his lessors)
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