As our investigation proceeded, the models under review became less and less "neat;" yet, in the midst of the diversity of applications of theories, a fil conducteur can stil be found which unites them and which makes, at the same time, the opposition of world-views more and more apparent. The most striking model is the "structuralist" one. On the basis of the same data concerning the nature and processes of man, culture, and society, structuralism (which is proposed as a method, yet used as a philosophy or even ideology) has invaded most of the human sciences.