  Motivated by the recently proposed connection between N=2 BPS black holes and
topological strings, I study the attractor equations and their interplay with
the holomorphic anomaly equation. The topological string partition function is
interpreted as a wave-function obtained by quantizing the real cohomology of
the Calabi-Yau. In this interpretation the apparent background dependence due
to the holomorphic anomaly is caused by the choice of complex polarization. The
black hole attractor equations express the moduli in terms of the electric and
magnetic charges, and lead to a real polarization in which the background
dependence disappears. Our analysis results in a generalized formula for the
relation between the microscopic density of black hole states and topological
strings valid for all backgrounds.
