The philosophical underpinning of the realism of documentary photography has been a positivism that assumes the unproblematic existence of an observable reality, a neutral, detached and unified observing subject, and a form of inductivism derived from sensory experience.
This is documentary photography's originary and formative way of thinking, and it underpins the way that the focus of the camera apparatus assumes the sovereignty of geometrical perspective -- Euclidean geometry as the cone of vision. This convention of perspective centres everything on the eye of the disembodied beholder standing outside the field of vision.
This is deemed to be a natural representation, the way things really looked, the way that we see, and the way things really are. The world is clear and distinct even at the margins, and the entire field of vision is measurable and visible. It's main flaw is that it ignores interpretation and meaning. The picture was objective and truthful, but it was an interpretation of the meaning of this drosscape.
It was the emergence of digital technology that ruptured this mode of knowledge, representation and photographic realism, not the philosophical critiques of positivism by hermeneutic philosophers such as Wilhelm Dilthey. In this tradition understanding is not pursued ‘vertically’ by layering beliefs on top of foundations, but rather ‘circularly,’ in an interpretive movement back and forth through possible meanings of our presuppositions that by turns allow a matter to come into view. In this, the pursuit of understanding does not build ‘higher and higher;’ it goes ‘deeper and deeper,’ gets ‘fuller and fuller,’ or, perhaps ‘richer and richer.’
Nietzsche made art central, explored how art misrepresents reality, emphasised the role that art might play in enabling us positively to ‘revalue’ the world and human experience, accords to art the potential for functioning as the counter-movement to general nihilism, and reflected on the nature and method of interpretation throughout his published and unpublished writings. Yet he had no impact on the liberal tradition of documentary photography.