Reducing the plot to barely nothing and no special effects, Tarkovsky relied on his materialistic style to create a unique nonlinear visual experience. Outside reality, just like the Zone, wouldn't be more coherent in its maddening uncertainties.
Patience! At first all sporadic, expanding lives connected with chance, somehow fall into place and tied together with the earthquake in the end and with the core of human selfishness (of victims and victimizers alike). How does one come out of an Altman film feeling positive?