It is familiar to psychiatrists because of the way that psychopaths use displays of lack of feeling – a jokey, gamesy, but chilling, indifference to subjects that spontaneously call forth strong human emotions – to gain control of others and make them feel vulnerable.
Art is a tool of emotion and is purposefu when it successfully shares/translates an emotion from one to another. It is a right hemispheric equivelant to the left hemispheric abstraction of words.
The cruelty is in the degree with which that emotional transmission is permitted to be or minimised. The latter is the role of the psychopath and school bully refered to here.
Consider the roleplay exhibited in the scene in the film, Inside Out, where Sadness emotes with BingBong whilst Joy attempts to dissemble the sittuation with 'playful' comments that in contrast with Sadness' response increasingly fell like jibes.
