When Susan Sontag published On Photography in 1977, photographs still circulated primarily as printed objects, slipped into albums, hung on walls or cut out of newspapers. Yet in observing this still-analogue world, Sontag grasped something that resonates closely with our own, now almost entirely digital world: photographs do not simply represent reality but profoundly alter the way we move through and experience it.

According to Sontag, photography introduced a new “grammar” and, above all, a new “ethics of seeing”, teaching us what is worth looking at, which aspects of the world should be preserved, and legitimising new subjects for our gaze. The camera does not simply record what we see: by selecting particular fragments of reality, it helps shape the way we see. To photograph is to cut out a portion of reality and separate it from its surroundings, producing an image that appears before us as evidence that this person existed, that this place was visited or that this event took place. Compared with a painting or a written description, photography therefore seems to maintain a more direct relationship with the world, since something must actually have been present before the lens for the image to come into being.

Yet this status as witness does not give photography the ability to make what it witnesses intelligible. Every photograph results from a series of choices: where we look from, when we press the shutter, what we include within the frame and what we leave outside it. None of these choices is apparent in the photograph itself. By photographing the same scene several times, we can therefore produce different, even contradictory versions of it, depending on the choices we make. Each shows us that something was, without being able, on its own, to tell us why it happened, what forces brought it about or what will happen next. Photography thus offers us a visible surface while concealing the network of relationships that made it possible.

From this characteristic arises the ambiguity Sontag emphasises: photography brings the world closer while simultaneously keeping it at a distance, allowing us to participate in an experience while also shielding ourselves from it. This is what happens, for instance, when a tourist encounters an unfamiliar place and the camera immediately gives them something to do, through a sequence of actions—framing, photographing, moving on—that gives the experience a recognisable form and thereby reduces its uncertainty. While photography may initially serve to certify that the journey really took place, it can gradually become the very principle by which that journey is organised, leading us from photographing what we encounter to seeking out what might make a good photograph. Experience is then lived partly in anticipation of the image it might produce, making certain situations seem more real because they can be photographed, and others less significant because they do not lend themselves as effectively to representation. We do not need to have a camera in our hands for this effect to take hold: once we have internalised its grammar, we begin involuntarily to see photographically, isolating details, imagining compositions, and assessing places, bodies and experiences according to their potential to become images.

Photography has therefore expanded the realm of the visible, revealing how an ordinary object, an empty street, a worn surface or an involuntary gesture can contain unexpected forms, and in doing so extending the realm of the “beautiful” to subjects and objects not traditionally considered as such. Yet this democratisation of the gaze also makes everything potentially available: if anything can become compelling once transformed into a photograph, then anything can also be collected, classified and consumed through its images. The consequences of this transformation become particularly apparent when photography depicts violence and suffering—war, crime, illness or poverty—because we often attribute to such images the power to raise awareness, as though seeing already meant understanding, and as though exposure to the pain of others could automatically produce a moral response. For Sontag, an image can reinforce an opinion we already hold, give a face to an event or make tangible a violence that had previously remained abstract. Yet without a context capable of explaining what it shows, it risks reducing a complex history to an intense but fleeting emotion.

The shock produced by images is itself destined to fade. While a disturbing photograph may become deeply imprinted on our memory, repeated exposure to similar images does not necessarily increase our capacity to respond. Instead, it can gradually transform the exceptional into something familiar, which slowly ceases to affect us. The proliferation of images thus produces a peculiar combination of proximity and indifference: we can gain access to an immense range of experiences lived by others without this availability necessarily translating into a greater capacity to understand them.

In response to this phenomenon, Sontag argues for the need to develop an “ecology of images”. The expression seems more urgent than ever today, particularly if we understand ecology not simply as an invitation to produce and consume fewer images, but also as a way of understanding the relationships we form with them: the influence they exert upon us and the transformations they bring about in our perception of the world. To think about images ecologically, then, means asking not only what they represent, but also what imaginaries they make possible, what desires they feed, how they solicit and disperse our attention, and which other forms of embodied experience they ultimately come to replace.