  We show that a ``fragmented Bose condensate'' in which two or more distinct
single-particle states are macroscopically occupied by the same species of
boson is inherently unstable to the formation of a conventional Bose condensate
whose macroscopically occupied state is a linear combination of the
``fragments'' with definite relative phases. A related analysis shows that a
reproducible relative phase develops when two initially decoupled condensates
are placed in contact.
