  Our purpose here is to introduce the idea of viewing the spacetime as a
macroscopic complex system which, consequently, cannot be directly quantized.
It should be thought of as a collection of more fundamental "microscopical"
entities (atoms of geometry), much like a solid system, in which an atomic
(classical) structure must be first recognized in order to ensure a correct and
meaningful quantization procedure. In other words, we claim that the classical
limit from a quantum theory of gravity could not give a four dimensional
Einstein spacetime directly, but requiring {\it a further} macroscopical limit.
This is analogous to a material medium, whose complete description does not
come from any quantized field.
  We also discuss a possible realization of this hypothesis for black hole
spacetimes.
