Corten steel sheets, like two pages of a book, are engraved with messages. Symbols and ancient alphabets from different cultures begin this process. These “witnesses” are “from here and elsewhere “recalling” the evolution of man. Above the tablets emerge two figures: that of the one who instructs and that of the one who receives. This process shows the link between decryption of the past and our new ways of transmitting and understanding knowledge, the code being an integral part of historical decoding.