He first made a name for himself as an artist with a collage he placed in front of the Parliament of Norway in 1965, titled "From a report from Vietnam: Children are splashed with napalm.
However Stockholm's social services wanted it clarified whether Slettemark was an ordinary unemployed person, or a patient with a mental illness.
Slettemark insisted that he was an artist, but was diagnosed borderline, and received a prescription for Hibernal (tablets for treatment of psychosis).
During the happening "Lecture in the art of falling", he balanced on a line in Stockholm, visualizing his three years of conflict with Swedish psychiatry.
The pun is lost in English, but inspired Slettemark to spend half a year constructing the costume, complete with inlaid sound from a television jackpot programme.