  By a pure logical framework we mean a framework which does not rely on any
particular formal calculus. For example, Metamath is an instance of a pure
logical framework. Another example is the Russell system
(https://github.com/dmitry-vlasov/russell). In this paper, we describe the
proof search algorithm used in Russell. The algorithm is proved to be correct
and complete, i.e. it gives only valid proofs and any valid proof can be found
(up to a substitution) by the proposed algorithm.
