"Since every photograph is contingent (and thereby outside of meaning), Photography cannot signify (aim at generality) except by assuming a mask. It is this word, which Calvino correctly uses to designate what makes a face into the product of a society and its history. As in the portrait of William Casby, photographed by Avedon: the essence of slavery is here laid bare: the mask is the meaning, insofar as it is absolutely pure (as it was in the ancient theater). This is why the great portrait photographers are great mythologists: Nadar (the French bourgeoisie), Sander (the Germans of pre-Nazi Germany), Avedon (New York´s “upper crust”).
Yet the mask is the difficult region of Photography. Society, it seems, mistrusts pure meaning: It wants meaning, but at the same time it wants this meaning to be surrounded by a noise (as is said in cybernetics) which will make less acute. Hence the photograph whose meaning (I am not saying its effect, but its meaning) is too impressive is quickly deflected; we consume it aesthetically, not politically. …
If we except the realm of Advertising, where the meaning must be clear only by reason of its mercantile nature, the semiology of Photography is therefore limited to the admirable performances of several portraitists. For the rest, with regard to the heterogeneity of “good” photographs, all we can say is that the object speaks, it induces us, vaguely to think. And further: even this risks being perceived as dangerous. At the limit, no meaning at all is safer: the editors of Life rejected Kertész´s photographs when he arrived to the United States because, they said, his images “spoke too much”, they made us reflect, suggested a meaning –a different meaning from the literal one. Ultimately, Photography is subversive not when it frightens, repels or even stigmatizes, but when it is pensive, when it thinks".
-Roland Barthes, Camera Lucida (To Signify) (trans. Richard Howard, Hill and Wang).