On the formation of views, The theory and technical methods of conservation have influenced the activities of many theorists and practitioners of various nations. These views changed in different periods of the history of conservation, depending on political conditions, ideological and economic.
In the initial period (until the first half of the nineteenth century), restorers, who were mainly architects and builders, they considered, that extending the life of a monument does not consist in fixing the embedded materials and structures, but on the maintenance of its shape and form. Therefore, the only radical way of securing the destroyed monuments was ... the dismantling of weak structures and the introduction of new. In this case, without respect for the historical and scientific values of monumental substances, instead of removing the causes of evil, strengthen, stabilize and consolidate historic links at risk, they demolished them and replaced them with structural elements and forms proper to the current of their time. Here, in many cases, materials that were not in line with the spirit of the era were used indiscriminately, without taking into account their technological properties, without proper calculation of their strength. More than once, the robots were far from technically correct, as a result, these objects or their fragments not only lost their historic character, but they were also subject to further destruction. This type of procedure resulted mainly from insufficient knowledge of the architecture and construction systems of buildings from bygone eras at that time.
A bit later, the efforts of the conservators aimed primarily at achieving artistic harmony in the monument, unity and purity of style, ignoring its structural features. The action of changing the shape and construction forms as well as removing stylish historical layers has begun. This direction was named] purism or otherwise - the direction of stylish purity.
This direction caused a lot of damage and devastation to the stock of historic buildings. It favored the use of alterations and any interpretation of architectural compositions, which led to a complete distortion of the former appearance of the preserved building, as well as its structural arrangement and allowed for the multiplication of unfortunate forgeries, especially in gothic forms.
At the end of the 19th century, this trend was opposed by the conservator's view aiming at preserving the monument in such a stud, in which it was given to us. Representatives of this direction were careful, that almost every monument of construction or architecture bears layers on it, tj. traces characteristic of the work of several different style eras. Hence, they postulated the preservation of these values in the spirit of historical evolution as necessary. This trend has been called historicism, I The desire to maintain the elements and structures accompanying the creation of an architectural work favored the method of recreating historical forms in materials analogous to those existing in a monument. In this way, new fragments were created, indistinguishable from the authentic ones.
Scientists and archaeologists drew attention to the harmfulness of the above-mentioned courses of action for science and cultural history. They requested, that the historic values of brick buildings lie not only in their stylish features, but also in all the accompanying elements of the creation of the work in the past, and above all in the construction materials used and in technical and organizational skills, that can be learned through scientific research. Ignoring the results of these studies in conservation work inevitably leads to a distortion of the laws, which ruled the construction systems used in a given historical epoch and as a result - to the erroneous dispositions of conservation concepts.
Influenced by critical polemics of experts and lovers of monuments at the beginning of the 20th century, against the background of various contradictions, a new view on the methods of conservation of architectural monuments is born: it does not exclude the possibility of making logical changes, transformations or additions, if they are dictated by technical or operational needs, especially if they contribute to slowing down the pace of destruction or are necessary to preserve the life of the monument. However, the use of this type of treatment was conditioned by this, that the new elements introduced into the structure of the monument will avoid the demolition of the historic work and will have a contemporary character, aesthetically harmonizing with the old forms.