Social media's currency is the single photograph. Whereas, every time I look at a photograph, I look at twenty or thirty photographs. I'm looking for a narrative. And that's a different kind of construct. If you're a poet and you put a line from your poem online, "The trees bending over gracefully," or something, you can get a tick. But that has nothing to do with your longer poem.

There was a time, right up until the end of the Second World War and beyond, when white people in Europe thought that they basically owned the world and that everybody else was a sort of servant, or a curiosity, or whatever. And that informed 99 percent of the photographic practice that was done. Without being able to address that, I felt I would have failed in my attempt to explain what the urge to document is.

Good photographs aren't just complex. They are enigmatic. Images are beguiling. And the way they play into our psychology, into our visual cortex, is something we still don't understand.

What people that are professionals in the art world - both in literature and the other arts - always try to do is to recognize the feasibility of making the transition from the particular to the general - to make the transition from the portrait of one postman - to take Van Gogh, for example, to something that is every postman. That synecdotal transition that most selfies don't make. But we who live in this world, and not simply in our private realities, understand that that's the transition our art has to make.

My current project was shot on film, and because of that I've spent my entire day removing dust-specks from negatives. You wouldn't have to do that on digital because you don't get dust on the scanner. I say to myself, "Why am I doing this all day?" I could have just bought a digital camera and I wouldn't have to remove dust-specks ever again. But when you move closer to a film image, it has a real truth to it. And I really like that.

Well, people from the "me" generation use photography to show off what they are doing, to show the world themselves and their friends. Those sort of diarized accounts have always been there. But the phenomena of making those diaries public is new, isn't it?

We create these walls between fact and fiction, but often the difference between the two is as little as that between a real name and a pseudonym. So I'm not sure about those walls - certainly not in the realm of visual arts.