Is art an inherently isolating thing? People connect over their viewpoints on art, sharing the experience of a particular movie, but I think the fundamental nature of art is something like what Harry Caul experiences in Francis Ford Coppola's 1974 film The Conversation--an examination of human nature that compels the isolation of the voyeur.
Whether or not Coppola meant for his film to be a metaphor for the nature of art, I don't know, but it's not hard to see Caul's compulsion to examine and illuminate humanity without participating as a metaphor for a film director. Caul, played by Gene Hackman, is a freelance surveillance expert, and as the film opens he and two partners are conducting a complicated operation to spy on a man and woman in Union Square in San Francisco. Harry's a man who obsessively keeps to himself, reluctant to divulge any personal information to his partners, one of his partners doesn't even know the city he'd lived in previously to San Francisco until he's informed by one of Caul's colleagues.
Teri Garr appears in the film for one scene as a woman Caul is supporting, paying the rent for her small apartment. She's in love with him even though he tells her nothing about himself, not even his job. She is very much a kept woman. When she leaves him, it's indicated it's probably because she had no reason to think he loved her back. She doesn't realise or accept that the anonymity Harry achieves in their intimacy is an enormous part of what he needs from her.
He's a devout Catholic, like Coppola, and we learn he feels guilty about information he obtained by surveillance that may have led to someone being killed. He's beginning to fear his current assignment may be a similar setup, which is why he obsessively listens to the tape of the couple at Union Square over and over.
In one of my favourite scenes, Harry dreams of seeing the woman from Union Square walking above him on a small hill, through fog, and he asks her questions as he tries to see her, receiving no response. It's like an artist trying to find out about human nature. "To reveal art and conceal the artist is art's aim" as Oscar Wilde said, and we find that in obsessing over the limited information he has, Harry becomes creative with it without meaning to and the movie also becomes about the unavoidable difference between perception and reality.
Harry Caul's one of the best, most interestingly portrayed characters I've seen in a movie. His horror at the idea of being a character in life's drama while simultaneously wishing to gain wisdom about people could be described as an Apollonian addiction. As such, the film functions as a great tragedy, and as a film noir--Harry cannot avoid making decisions that effect reality. And he can never definitively have the answers he will always be compelled to seek--that's an artist.