While Charles is a fictional character for the film, the film's depiction of Nash's struggles with schizophrenia is largely based on his real-life experiences.
It's important to remember that:
* Nash did experience hallucinations: The film accurately portrays the presence of hallucinations as a symptom of his illness.
* The specific identities of his hallucinations are less clear: There's no public record of specific names given to his hallucinations.
* The film takes creative liberties: The film focuses on the central role of one hallucination, Charles, for storytelling purposes.
Ultimately, the film offers a glimpse into the complex and personal nature of schizophrenia, but it's crucial to understand that it's a dramatization and doesn't necessarily reflect the specific experiences of every individual with the illness.