Barthes distinguishes erotica from pornographic photographs as follows. "The Photograph is unary when it emphatically transforms "reality" without doubling it, without making it vacillate (emphasis is a power of cohesion) : no duality, no indirection, no disturbance. The unary Photograph has every reason to be banal, "unity" of composition being the first rule of vulgar (and notably, of academic) rhetoric: "The subject," says one handbook for amateur photographers, "must be simple, free of useless accessories; this is called the Search for Unity." News photographs are very often unary (the unary photograph is not necessarily tranquil). In these images, no punctum: a certain shock-the literal can traumatize -but no disturbance; the photograph can "shout," not wound. These journalistic photographs are received (all at once) , perceived. I glance through them, I don't recall them; no detail (in some corner) ever interrupts my reading: I am interested in them (as I am interested in the world) , I do not love them. Another unary photograph is the pornographic photograph (I am not saying the erotic photograph: the erotic is a pornographic that has been disturbed, fissured). Nothing more homogeneous than a pornographic photograph. It is always a naive photograph, without intention and without calculation. Like a shop window which shows only one illuminated piece of jewelry, it is completely constituted by the presentation of only one thing: sex: no secondary, untimely object ever manages to half conceal, delay, or distract . . . A proof a contrario: Mapplethorpe shifts his close-ups of genitalia from the pornographic to the erotic by photographing the fabric of underwear at very close range: the photograph is no longer unary, since I am interested in the texture of the material." -- Source of annotation: Marvin or Ruth Sackner.