The starting point of all thinking about the past and our relation to the past must be that it is irreversible. This sounds almost ridiculously self-evident. Nevertheless it is exactly this fundamental characteristic which is creating the problems as well as the possibilities in the use of history. 

The irreversibility of the past somehow plays with us. On the one hand it is in the nature of the irreversibility that we cannot get into the time which has passed. It has just gone. Finito! There seems to be absolutely nothing we can do about it. Then on the other hand we sense the traces of the past everywhere.

It begins with our own memories and normally goes on with family memories, and then the collective memories of the community, the country and so on. In this way the past becomes extended to time before our own and therefore also before our personal memories.