How Buildings Learn by Stewart Brand is a really great read about the underlying processes that govern the evolution of buildings over time.
Preservation has become the best carrier of that moral force architecture needs if it is to have value beyond shelter.
Why are old buildings more freeing? They free you by constraining you.
It is much easier to continue than to begin. Less money is needed, as well as less time, and fewer people are involved, so fewer compromises are necessary.