What remains of a civilization is its art and architecture. While wars and search for power are ephemeral, the buildings endure. This is illustrated in the way a Hindu temple is decorated. The lowest band of the facade is carved with battle scenes and chaos, while higher up appear scenes of everyday life. Higher still are images of the gods while at the very top, there is no decoration signifying the moment of truth where no image exists.
One of my favorite books is 'The pleasure of ruins' by Rose Macaulay. Ruins seem to encompass both joy and melancholy more than complete buildings. It is perhaps the reflection of death that makes them special.
My approach to design has been to find the eternal. In the modern world, this may be a difficult task. Buildings that address both time and space appear to be more meaningful.