To use a computer to automatically process knowledge in the same manner as Prolog, the knowledge being expressed in a format wherein variables are embedded in natural language, and to achieve comprehensive deduction and solution searching at the predicate logic level. As in the input of Prolog “facts,” “rules,” and “goals,” in the present invention a person uses character types, delimiters, or escape characters to distinguish the constant portions and the variable portions of content that is equivalent to “literal” in Prolog and inputs the content into a computer. The computer performs automatic unification and/or automatic derivation on text included in the input while treating variables as material that could span the boundaries of the subject, predicate, etc. of the text.
