Breitwieser has been stealing art for around six months, which is seen as a severe psychological disorder by some.
However, psychotherapist Schmidt believes there is no criminal psychosis to cure, a view shared by other therapists.
Despite court-ordered examinations by therapists, Breitwieser rejects any categorization of himself as mentally unwell, perceiving himself as a "seer" deserving of stolen art and seeing his crimes as victimless.
Various psychologists, including Schmidt, have insinuated that Breitwieser is immature, coddled, and narcissistic, but do not see indications of clinical insanity or disability in him.
While displaying signs of antisocial and narcissistic personality disorders, therapists still have no solid explanation for the roots of Breitwieser's criminality.
Breitwieser and his girlfriend Anne-Catherine, who was found to have a "fragile personality" and be susceptible to manipulation, stole art at a highly accelerated pace.
Breitwieser justifies his thefts by pointing out that art has always been stolen throughout history, from ancient civilizations to modern art dealers and more.
From his viewpoint, the art world is inherently corrupt, with everyone in it being a thief in some way - whether through legal means or otherwise - and he views himself as a self-proclaimed hero in this narrative he has constructed.