STEVENS followed up on the paradoxical analogy that BESSER alluded to in the example of the MARC records, namely, the formats that are the same except that they are different. STEVENS drew a parallel between document-type definitions and MARC records for books and serials and maps, where one has a tagging structure and there is a text-interchange. STEVENS opined that the producers of the information will set the terms for the standard (i.e., develop document-type definitions for the users of their products), creating a situation that will be problematical for an institution like the Library of Congress, which will have to deal with the DTDs in the event that a multiplicity of them develops. Thus, numerous people are seeking a standard but cannot find the tag set that will be acceptable to them and their clients. SPERBERG-McQUEEN agreed with this view, and said that the situation was in a way worse: attempting to unify arbitrary DTDs resembled attempting to unify a MARC record with a bibliographic record done according to the Prussian instructions. According to STEVENS, this situation occurred very early in the process. WATERS recalled from early discussions on Project Open Book the concern of many people that merely by producing images, POB was not really enhancing intellectual access to the material. Nevertheless, not wishing to overemphasize the opposition between imaging and full text, WATERS stated that POB views getting the images as a first step toward possibly converting to full text through character recognition, if the technology is appropriate. WATERS also emphasized that encoding is involved even with a set of images. SPERBERG-McQUEEN agreed with WATERS that one can create an SGML document consisting wholly of images. At first sight, organizing graphic images with an SGML document may not seem to offer great advantages, but the advantages of the scheme WATERS described would be precisely that ability to move into something that is more of a multimedia document: a combination of transcribed text and page images. WEIBEL concurred in this judgment, offering evidence from Project ADAPT, where a page is divided into text elements and graphic elements, and in fact the text elements are organized by columns and lines. These lines may be used as the basis for distributing documents in a network environment. As one develops software intelligent enough to recognize what those elements are, it makes sense to apply SGML to an image initially, that may, in fact, ultimately become more and more text, either through OCR or edited OCR or even just through keying. For WATERS, the labor of composing the document and saying this set of documents or this set of images belongs to this document constitutes a significant investment.