I'm reading a great book at the moment called 'Photographs Not Taken'. It's a collection of essays by photographers on missed opportunities and the ethical problems that they face.
This is part of the introduction by Lyle Rexer:
...the anecdotes collected here, personal as they are, reflect an aspect of the growing "crisis" of photography, a crisis that has to do with the self-consciousness of the genre and the broader ambivalence about the role of images in a media-saturated world. Yes, photography is a kind of atavism, a by-now instinctive response to the technologized, spectacular world, a mad cataloging that often resembles nothing so much as a vast collection of toenail cuttings. Yet these days every photograph taken by people who do it for a living arrives inside a set of quotation marks, a bracketed form of perception that says: "Don't trust me!" and "Should I really be showing you this?" and "Should you really be looking?" Above all, "does it matter?"

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