The activity of thought is deeply perplexing. Anyone resistant to its consignment to the domain of sub-personal psychology, or to quasi-behaviouristic elimination, needs to address such matters as why it is that thinking seems to elude capture in consciousness, and what the nature of self-ascription may be. This paper takes up from an earlier discussion by Claudio Costa (‘ “I’m Thinking” ’Ratio 2001) and argues that his account of thinking is flawed. It also argues, in opposition to Costa, that self-reflexivity is real and is required to account for the ownership of thoughts. Finally, it identifies an argument from self-awareness to the conclusion that the subject of thought is not a material object.