Decision of the attribute reductivity about concept lattices

Introduces the concept of Galois connection by which concept lattices are studied further.The two concept lattices which are concept lattice isomorphic with each other are lattice isomorphic with each other.In order to find out more concise and reasonable reduction algorithm,four kinds of decision theorems of consistent set are proposed in general formal context(i.e.attribute sets and object sets are finite or infinite),which generalize the present results.It is illustrated by an example that the reduction needs not exist in general formal context.