To cognize is to know, and to have a cognitive capacity is to have a capacity (ability) which seems to generate or require knowledge.  Cognitive science seeks to explain the cognitive capacities, of humans, animals, and possibly machines.  However, the primary thrust of research in cognitive science is directed towards explaining human cognitive abilities.  More recently, theorists have devoted attention to consciousness and emotion.  The classic approach to explaining cognitive capacities within cognitive science has two foundational theses; The "Computational Theory of Cognition" (CTC) and the "Representational Theory of Intentionality" (RTI).  Together these theses dictate the explanatory structure of cognitive science.  The CTC characterizes cognition as the computation of complex functions on representational states, where computation consists in performing operations defined over representational states.  These operations can be rule-based manipulations of  syntactic strings as in traditional artificial intelligence, or the weighted passing of activation as in connectionist models.  The RTI asserts that mental states have intentionality (are about the world/have content) in virtue of a representation relation holding between the world and those states.  There are three conceptually distinct (though not necessarily temporally distinct) stages.  CTC/RTI framework portrays cognizers as receiving input through sensory organs and/or memory and generating outputs in the form  of memories, inputs to other processes, and/or motor response commands.

Cognitive scientists hotly debate the exact nature of the computational processes involved in cognition.  On the one hand, many theorists favor Turing-compatible computation and its development in contemporary computer science and mathematics.  On the other hand, many theorists favor dynamically described state transitions (ex. Connectionism).   A similar theoretical dichotomy fosters debate in the literature on representation.  The two general theoretical approaches towards a theory of representation are " Nomic (law-like) Covariation" and "Functional Role Semantics".  Neither theoretical approach regarding the representation relation has gained general acceptance as the theory presupposed by the RTI.  However, there are several agreed-upon constraints for a theory of representation.  First, the representation relation must be consistent with the physicalistic nature of cognitive science.  Second, the relation must be present and explanatory in accepted explanations within cognitive science. (an appropriate characterization of "accepted" explanations is somewhat controversial).  Philosophers particularly would also like to see the accepted theory of representation explain many of the widely accepted properties of belief.  Block (1986) and Fodor (1988) provide excellent discussions of the potential problems, the solutions to which many Philosophers hope to find in a theory of mental representation.