  In recent years there has been a developing realization that the interesting
large--scale structure of voids, ``pancakes", and filaments in the Universe is
a consequence of the efficacy of an approximation scheme for cosmological
gravitation clustering proposal by Zel'dovich in 1970. However, this scheme was
only supposed to apply to smoothed initial conditions, and its efficacy for
hierarchical clustering has not been justified. We show that this is explained
by the fact that the gravitationally evolved potential from N--body simulations
closely resembles the smoothed potential of the initial conditions. The
resulting ``hierarchical pancaking" picture combines features of the former
Soviet and Western theoretical pictures for galaxy and large--scale structure
formation.
