  The classical nucleation theory of Becker, D\"{o}ring and Zeldovich is
compared with the Langer coarse-grained field approach to the nucleation
phenomenon. Both formalisms have been applied to the condensation from a
supersaturated vapor. It is shown that the nucleation rate derived in the
classical theory can be expressed in a form equivalent to that of the field
nucleation theory. This equivalence serves as an explanation of the puzzling
fact that the numerical predictions of both theories for condensation of Xe and
CO$_2$ are almost identical though the standard analytical expressions for the
nucleation rates are different. The results obtained can help to link the
theories of nucleation and their approximations.
