He pleads for a postlinguistic, postsemiotic "iconic turn", emphasizing the role of "non-linguistic symbol systems". Instead of just pointing out the difference between the material (pictorial or artistic) images, "he pays attention to the dialectic relationship between material images and mental images". According to Dennise Bartelo and Robert Morton, the term "iconology" can also be used for characterizing "a movement toward seeing connections across all the language processes" and the idea about "multiple levels and forms used to communicate meaning" in order to get "the total picture” of learning. "Being both literate in the traditional sense and visually literate are the true mark of a well-educated human." For several years, new approaches to iconology have developed in the theory of images. This is the case of what Jean-Michel Durafour, French philosopher and theorist of cinema, proposed to call "econology", a biological approach to images as forms of life, crossing iconology, ecology and sciences of nature. In an econological regime, the image ("eikon") self-speciates, that is to say, it self-iconicizes with others and eco-iconicizes with them its iconic habitat ("oikos"). The iconology, mainly Warburghian iconology, is thus merged with a conception of the relations between the beings of the nature inherited, among others (Arne Næss, etc.) from the writings of Kinji Imanishi. For Imanishi, living beings are subjects. Or, more precisely, the environment and the living being are juste one. One of the main consequences is that the "specity", the living individual, "self-eco-speciates its place of life" ("Freedom in Evolution"). As far as the images are concerned: "If the living species self-specify, the images self-iconicize. This is not a tautology. The images update some of their iconic virtualities. They live in the midst of other images, past or present, but also future (those are only human classifications), which they have relations with. They self-iconicize in an iconic environment which they interact with, and which in particular makes them the images they are. Or more precisely, insofar as images have an active part: "the images self-eco-iconicize their iconic environment"." "Studies in Iconology" is the title of a book by Erwin Panofsky on humanistic themes in the art of the Renaissance, which was first published in 1939.