Tectology is a term used by Alexander Bogdanov to describe a discipline that consisted of unifying all social, biological and physical sciences, by considering them as systems of relationships, and by seeking the organizational principles that underlie all systems. Bogdanov invented an original philosophy that he called tectology which is now regarded as a precursor of systems theory and related aspects of synergetics. The word tectology was developed by Ernst Haeckel, but was used to a different purpose by Bogdanov.