In this chapter we establish what it is for something to be implicit or explicit. The approach to implicit knowledge is taken from Dienes and Perner (1999), which relates the implicit-explicit distinction to knowledge representations. What it is for a representation to represent something implicitly or explicitly is defined and those concepts are applied to knowledge. Next we will show how maximally explicit knowledge is naturally associated with consciousness. We argue that each step in a hierarchy of explicitness is related to the unity of consciousness and that fully explicit knowledge should be associated with a sense of being part of a unified consciousness. New evidence indicating the extent of people's implicit or explicit knowledge in an implicit learning paradigm will then be presented. This evidence will indicate people can be consistently correct in dealing with a context-free grammar while lacking any knowledge that they have knowledge. 1.

In this chapter we establish what it is for something to be implicit. The approach to implicit knowledge is taken from Dienes and Perner (1999) and Perner and Dienes (1999), which relates the implicit-explicit distinction to knowledge representations. To be clear about exactly what our claims are we first discuss what a representation is, what it is for a representation to represent something implicitly or explicitly and apply those concepts to knowledge. Next we show how maximally explicit knowledge is naturally associated with consciousness (according to the higher order thought theory). Then we discuss the relationships between explicit knowledge and metacognition, where metacognition is considered in terms of both its monitoring and control aspects, to shed light on conscious and unconscious perception, episodic memory, and volitional control. We will then show how implicit learning should be viewed in metacognitive terms, and conclude that people' s relative lack of metaknowledge in implicit learning paradigms justifies the claim that people have acquired genuinely implicit knowledge. In Izaute, M., Chambres, P., Marescaux, P.-J. (Eds), Metacognition: Process, function, and use. Dordrecht, Netherlands: Kluwer Academic Publishers, forthcoming. 1.