Aquanet and its successor, VIKI, are spatial interpretive hypertext systems, each with a slightly different emphasis. Aquanet focuses on collaborative sense-making activities like argumentation and analysis; the system allows users to create and manipulate complex graphical knowledge structures. From observing Aquanet in use, we found that informal representations are crucial to coaxing out partially formed, emerging interpretations. One of Aquanet's unexpected strengths was the ability it gave people to express interpretations -- interpretations that were less than fully formed -- in terms of visual appearance or spatial positioning.
VIKI supports the ad hoc use of a visual symbol language so people can see and express structure as it becomes apparent to them. Because interpretation -- along with the concommitant act of organizing materials -- is opportunistic, users are not confined to a particular working style; they may work from gathered examples to develop structure, they can work schematically (the mode Aquanet enforced), or they may leave structure and meaning largely implicit. Thus, in VIKI, we hope to complement the ability to develop abstraction and reflect on and critique interpretive frameworks with the flexibility offered by ad hoc, visually salient representations and spatial hypertext.