  This paper describes the first-order logical environment FOLE. Institutions
in general, and logical environments in particular, give equivalent
heterogeneous and homogeneous representations for logical systems. As such,
they offer a rigorous and principled approach to distributed interoperable
information systems via system consequence. Since FOLE is a particular logical
environment, this provides a rigorous and principled approach to distributed
interoperable first-order information systems. The FOLE represents the
formalism and semantics of first-order logic in a classification form. By using
an interpretation form, a companion approach defines the formalism and
semantics of first-order logical/relational database systems. In a strict
sense, the two forms have transformational passages (generalized inverses)
between one another. The classification form of first-order logic in the FOLE
corresponds to ideas discussed in the Information Flow Framework (IFF). The
FOLE representation follows a conceptual structures approach, that is
completely compatible with formal concept analysis and information flow.
