Today, architecture in cities is at a great crossroads, cities have been occupied in a way never seen in the history of mankind. As architects we understand that the solution to the city's problems are densification, variability of use and a number of strategies that promote a change of direction in how we have been doing our cities. In response to this reality, this article raises the use of what we already have, the buildings of our cities, the preexistence.

This investigation focuses on "postproduction", a term typical of the audiovisual world but which, understood conceptually, has been used by various authors to refer to all the actions carried out on a work already produced and differentiates it from the work created since Zero, that is, a pre-existence works as a raw material. [1] At present, several architects already carry out works that are considered post-production, their projects place a new project on another, giving it new functions, scales, uses and spatialities, adding the pre-existing as solution to contemporary needs.

In this context Bourriaud defines pre-existence again, from his perspective of the artistic world through the idea of ​​Duchamp's “ready-made” due to the decontextualization value that resides in them. This decontextualization serves as a tool in the post-production of objects and, why not, buildings. This is evident when the post-production work is not a work of historical or patrimonial restoration, but rather is carried out on ordinary or common architectures, unnoticed architectures that, from post-production, gain relevance or solve problems in their environment.

Post-production manifests itself mainly from interventions by additions applied on preexistence as mechanisms of exploration and densification in an urban context; without limiting its applicability to other situations, environments and morphologies of the city already built.

The addition is defined as a fragment alien to the pre-existence, as a new project that is added to the existing building. It needs pre-existence to have a physical, instrumental, functional and formal support. The addition, due to its adaptability within the practice with limited economic means, the structural, formal and location freedom with respect to the built city and due to the potential reversibility of these interventions; it has the potential to be an applicable solution in practically all the preexistence of our contemporary cities.

POSTPRODUCTION

In Post-production: culture as a setting: ways in which art reprograms the contemporary world, Nicolás Bourriaud uses this term to refer to this contemporary trend of the use of preexistence for artistic production work. Text in which he also makes references to Marcel Duchamp's ready-made referring to: such artists who insert their own work into that of others, contribute to abolishing the traditional distinction between production and consumption, creation and copying, ready-made and original work . The material they handle is no longer raw material. ”[2].

Marcel Duchamp coined the term ready-made in 1915 to describe his found art. Duchamp assembled his first "ready-made", entitled Bicycle Wheel, in 1913, at the same time that his Nude Descending a Staircase attracted the attention of critics at the International Exhibition of Modern Art. “La Fuente”, a urinal that he signed with the pseudonym “R. Mutt ", confused the art world in 1917. In reference to this work, in the editorial of the magazine The Blind Man of 1917 it is said:" The fact that Mr. Mutt made or not "The Fountain" with his own hands it is irrelevant. He chose it, took an article from everyday life, and presented it in such a way that its utilitarian meaning disappeared under a new title and point of view. It created a new thought for that object ”. This reflection shows us the value of ready-made in the context of post-production, as objects taken from an original context, defunctionalized and converted into art, constructed to force the viewer to think. The problems that this type of art were mainly due to questioning the traditional aesthetic categories, instead of an object created by the artist, the public admired one already manufactured. Giving value to common or ordinary objects that consist of the common in daily life.

In the ready-made “an attitude that declined, from a strong critical position towards society, to produce new objects from scratch was evident; the novelty was obviated in the face of the predisposition to use, from a decided non-neutral position, pre-existing materials. ”[3] Bourriaud brings up Duchamp's readymades for having post-production as their main heir today and for the value of decontextualization and criticism that resides in them. And this, wouldn't it be the tool that we are currently needing to face increasingly inhabited cities? Decontextualization that in the post-production of objects and why not of buildings helps us to consider the work on preexistence as something new, a new city that literally emerges from the existing one.

In the contemporary city, architects must change our position when facing the project, from a perspective where we consider: what is new, what can be done? ", Towards one where we ask ourselves: what can be done with? "[4].

When making a relationship between the term post-production and architecture, we find that the term "post-production" coined by Bourriaud to refer to the premeditated use of preexistence in the artistic universe is something that to a greater or lesser extent has always been part of the history of the architecture from its very origins. Long before the 'ready-made', Greek and Roman architecture already took out of context (relocated and reprogrammed) previous material elements to form part of new constructions. Not only that, iconic buildings in the history of architecture –the Mosque of Córdoba, to name a few– “are physical reprogramming results of the passing of the centuries.” [5]

Therefore, when considering post-production as a strategy, we must understand that it is necessary to fine-tune the “new” architecture that links or takes over preexistence; To the extent that we can think that the way this architecture communicates is actually the articulating point of post-production as a design tool. In order to understand all these variables, we found the need for the production of an atlas where generic strategies for the use of preexistence together with additions can be presented; with the aim of spreading the possibility of using this tool, in contrast to the blank slate that has generated the excessive growth of our cities. This development will be seen in the investigation of the thesis related to the preexistence of my authorship and the need for its use as a basis for contemporary architecture.

[1] Nicolas Bourriaud, Post production: culture as setting: ways in which art reprograms the contemporary world (Buenos Aires, Argentina: Adriana Hidalgo, 2004).

[2] Bourriaud.

[3] José López, «Preferiendo do (almost) nothing in architecture: post-production through four actively lazy declines» (Doctoral Thesis, Universidad Politécnica de Madrid, 2017).
[4] Bourriaud, Post production.
[5] López.

Arch. March Pablo Cevallos.