what psychological diagnosis can be given to the phantom of the opera?

Post-traumatic stress disorder.

Discarded by his mother as a baby and sought out to be executed may be experiences that have induced PTSD.

Social anxiety disorder.

Shunned by society for his deformity, Erik takes refuge in solitude, thus social anxiety disorder.

i don't recall what axis it is, but he is clearly a sociopath and has an anti-social personality disorder.

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