The Original in the Case of Impermanent Objects
  Architecture rises above the earth where it is battered by the wind, rain and the elements. Naturally parts of these structures will collapse and the original sections of any structure will gradually be lost. In the case of stone architecture, they fall into ruins in such a way that the object itself exists even as the form crumbles. However, in the case of wooden architecture, if left to itself, the floor collapses, the roof caves in and after 50 years, there is no longer any trace of the structure. In other words, the ruins of a wooden structure cannot be left to continue, as is, in an exposed position. At some set interval, restoration work becomes necessary.
  When we look at the Main Hall (Kondo) of Horyuji, we immediately notice that many sections of the joinery and eaves have been replaced with new pieces of wood. Thus through the replacement of sections, the integrity of the entire structure is preserved. There are no missing sections, or lacunas as they used to be described in Europe. In the case of Nikko Toshogu, a major example of premodern religious architecture, the exterior exposed areas are covered with lacquer and paint, and there are many instances where these areas have been repeatedly repainted. However, the methods and particulars of such restoration work have often been maintained and continued. Experiments with preserving the current state in order to prevent flaking damage were not conducted until the relatively recent past.
  The philosophy that the act of restoration must strictly stop at the minimum of effect to the original state of the object derives from Europe, or from stone construct culture. Originals in wooden architecture are not limited to the object itself. In such cases they also consist of the architectural completeness of a structure, its form, its methods, and its finish.

Not "Preservation," Rather "Handing on to Future Generations": How Objects are Handed on in Wooden Architecture
  The concept of handing on wooden architecture as original objects to future generations emerged only in the modern era. Conversely, prior to the modern era, architecture was usually inherited by either rebuilding at set time intervals or dismantling and restoring. The idea of rebuilding at set time intervals originated at Ise Shrine, where it became a standard program of operation from the early inception of the main shrine buildings. Thus this restoration method was fundamental in the establishment of the Ise Shrine. On the other hand, prolonging a building's life through dismantling and repair involved a comprehensive structural reform, intrusive to its original parts, in most cases in the Edo period.
  Such acts were constrained by the concept of "preservation" in the modern era, and they were then rejected or regarded only as extreme examples. These methods can be appropriately called "handing on" architecture to future generations. They are not a case of object as original, but rather allow the replacement of objects, in order to hand on the original concept within architecture to future generations.

The Authenticity of Replacement
  It would seem that the meaning of authenticity in which the continuity of architecture itself is guaranteed must be reconsidered in the case of wooden architecture. Doesn't the "handing on" of wooden architecture involve not only the act of intentional "preservation" of form, methods and finish, but also a means of the unintentional preservation of such? It may be the case that "preservation" should be positioned as the modern means of "handing on." Even with replacement, authenticity is preserved. We must consider such methods in our concept of the original in wooden architecture.