Digital editions between embedded markup and external representation. A case study: Vespasiano da Bisticci’s Letters

Digital editions, in the field of humanities, are often based on formal internal annotation, generally expressed through embedded XML/TEI markup. XML-based markup systems, using the TEI Schema, represent thus the first step for the digital representation of textual structures. But the embedded markup does not seem convenient to describe all the possible latent features of the annotated elements and consequently of a text. Redundancy in markup could also produce errors in attributions and inconsistency. Moreover the hidden information, that rises naturally from the textual context, but also from the researcher/editor personal knowledge, cannot emerge. Especially the implicit relationships between annotated elements have to be declared in a formal way. Some case studies, regarding humanistic documents, show the importance of the creation of an external representation, in order to add depth and meaning to the description of some parts of the text and to establish possible complex relationships not only between annotated data elements, but also between the annotated text and other external Web-based existent resources. When this external representation is expressed in a formal way, according to a standard model like RDF and to shared ontological predicates, a knowledge base can be established, through which editor’s inferences can be expressed and new information emerge. From one hand implicit associations in the sources can then became explicit assertions and, from the other, a connection of distributed data on the Web, via Linked data, can help researchers in the interpretation of the deep meaning of concepts, phenomena and objects expressed inside the texts.