  Attempts to import dual-system descriptions of System-1 and System-2 into AI
have been hindered by a lack of clarity over their distinction. We address this
and other issues by situating System-1 and System-2 within the Common Model of
Cognition. Results show that what are thought to be distinctive characteristics
of System-1 and 2 instead form a spectrum of cognitive properties. The Common
Model provides a comprehensive vision of the computational units involved in
System-1 and System-2, their underlying mechanisms, and the implications for
learning, metacognition, and emotion.
