ABSTRACT
In J. Bermudez 2003b and 2009, in this chapter, the author proposed that certain types of thinking about thinking are only available to language-using creatures. He argues that generated interesting debate and useful criticisms help to refine and develop it. The author thinking about propositional attitudes is a much richer and more demanding cognitive phenomenon than thinking about perceptual states. It is only for propositional attitudes that the question of language-dependence arises. Moreover, the most widely discussed evidence for metacognition in the animal kingdom comes from studies of animals' degrees of "uncertainty" about their perceptual judgments. A number of experimental paradigms directly address the question of whether animals can think about thinking. In order to get the issues clearly in view, it is important to make some basic distinctions between different types of thinking about thinking.
