The example of a user reaching into and removing an object from an alternate reality highlights one of the more interesting design issues in ARK, namely the necessity to occasionally break with the highly literal physical world metaphor in order to provide useful functionality. Smith refers to this issue as the tension between magic and literalism in ARK [Smith 1987]. While using a hand which can grab physical objects is a highly literal component of the system, allowing a user to reach into a simulation and alter or remove objects with no regard to the physical laws currently at work in the environment clearly provides the user with what could be considered “magical” powers. The question of when to allow a magical event or action in ARK to conflict with the physical metaphor parallels a similar concern in the design of more traditional VPLs. In developing most VPLs, researchers have had to decide on the appropriate uses of text in their system. While it is possible to design a system which uses no text whatsoever, and such systems have been created, the resulting programs are often very difficult to read and understand. Most VPLs, even those which are completely visual, use text, at the very least, to label variables and functions in programs. Thus designers must face the same problem as was addressed in ARK. They must attempt to balance consistency of visual representation with usability.