Argus is the perception module. It has the ability to notice qualitative breaks in the subset of the environment it is paying attention to, thereby allowing it to produce a qualitative event to pass to Labyrinth. Argus monitors the plan in Labyrinth's active memory to determine what to pay attention to. Both parsing the environment and selecting where to attend increase the efficiency with which Icarus can deal with its environment. This becomes increasingly important as the architecture is scaled up to more complex environments. The attention mechanism used in Argus however limits the reactivity of the architecture by limiting the features that used to make decisions. The Argus module was never actually built with the full functionality described in the references and here.