It has already been said that Syd Barrett, founding member of the legendary band Pink Floyd, was one of the most relevant rock musicians to be affected by a psychosis. After the release of their debut album, Barrett's deteriorating mental health led him to leave the band at the young age of 22. Although his specific diagnosis was never disclosed, it is believed to be either schizophrenia or a psychosis resulting from his misuse of substances such as LSD and marijuana. His bandmates suffered his decline and blamed it on drug use and industry pressures.

Pink Floyd's discography is sparkled with references to mental illness. Brain Damage, the penultimate track of 1973's The Dark Side of the Moon, and 1979's album The Wall both refer to and describe mental struggles. Furthermore, Wish You Were Here, the band's ninth album, addresses themes of alienation and a greedy music business, and explicitly comments on their loss of Syd and their bereavement. Shine On You Crazy Diamond is an epic 26-minute-long progressive rock track written about and dedicated to Barrett; the song is split into parts – as if nodding to the etymological origin of the word ‘schizophrenia’ and the fractured self, nuclear to this disorder – and serves as bookends to the album. Roger Waters’ lyrics describe Barrett with certain psychopathologic prowess.

Different themes are intertwined among the verses: stardom and its effect on young musicians; a romanticisation of addiction and drug misuse as a means to find truth; and the narrator's observations on Barrett's psychotic symptoms. These are soaked in nostalgia and interspersed with cries of encouragement sung by a gospel-like choir (‘Shine on, you crazy diamond!’). Several lines describe possible symptoms. The song's opening verse, ‘Remember when you were young/You shone like the sun ( … ) Now there's a look in your eyes/Like black holes in the sky’ could be interpreted as a description of the vital change and the flat affect found in schizophrenia and other chronic psychoses. ‘Nobody knows where you are/How near or how far’ allude to both spatial and affective isolation, and this alienation is further emphasised by calling him a ‘stranger’. Other lines convey descriptions of hallucinatory phenomena describing Barrett as a ‘target for faraway laughter’ and a ‘seer of visions’. His behavioural change and disorganisation are outlined with terms like ‘raver’ and ‘random precision’. Finally, addressing him as a ‘prisoner’ summarises the condition he is confined to live in.

Despite the fact that none of the composers had any formal training on the subject Shine On You Crazy Diamond artfully depicts Syd Barrett's psychopathology, providing valuable insight into his mental struggles. It also serves as a heartfelt reflection of the profound loss felt by Barrett's long-time friends and bandmates, and explores the interplay between art and mental health.