Interdisciplinarity defines and discusses disciplinarian thinking in a world dominated by increasing complexity. Is interdisciplinarity the answer to the contradictions and paradoxes created by this situation? The nature of the interdisciplinarian activity is analyzed in this context and the author concludes that, while "practical interdisciplinarity" may at times be very successful, many interdisciplinarian activities lead to confusion and deep antagonisms between different intellectual "cultures." Interdisciplinarity as a "metadiscipline" remains still to be defined.