To explain how stimuli cause consciousness, we have to explain causality. We can't trace linear causal chains from receptors after the first cortical synapse, so we use circular causality to explain neural pattern formation by self-organizing dynamics. But an aspect of intentional action is causality, which we extrapolate to material objects in the world. Thus causality is a property of mind, not matter.

In a passive information processing system a stimulus input gives information, which is transduced by receptors into trains of impulses that signify the features of an object. The symbols are processed according to rules for learning and association and are then bound into a representation, which is stored, retrieved and matched with new incoming representations. In active systems perception begins with the emergence of a goal that is implemented by the search for information. The only input accepted is that which is consistent with the goal and anticipated as a consequence of the searching actions. The key component to be modeled in brains provides the dynamics that constructs goals and the adaptive actions by which they are achieved.

Neurodynamics of intentionality in the behavioral act of observation Intelligent behavior is characterized by flexible and creative pursuit of endogenously defined goals. It has emerged in humans through the stages of evolution that are manifested in the brains and behaviors of other animals. Intentionality is a key concept by which to link brain dynamics to goaldirected behavior. The archetypal form of intentional behavior is an act of observation through time and space, by which information is sought for the guidance of future action. Sequences of such acts constitute the key desired property of freeroving, semi-autonomous devices capable of exploring remote environments that are inhospitable for humans. Intentionality consists of (a) the neurodynamics by which images are created of future states as goals; (b) command sequences by which to act in pursuit of goals; (c) prediction of changes in sensory input resulting from intended actions (reafference); (d) evaluation of performance; and (e) modification of the device by itself in learning from the consequences of its intended actions. These principles are well known among psychologists and philosophers. What is new is the development of nonlinear mesoscopic brain dynamics, by which to apply chaos theory in order to understand and simulate the construction of meaningful patterns of endogenous activity that implement the perceptual process of observation.