Abstract. In psychology, thinking is typically studied in terms of a range of behavioral or physiological parameters, focusing, for instance, on the mental contents or the neuronal correlates of the thinking process proper. In the current article, by contrast, we seek to complement this approach with an exploration into the experiential or inner dimensions of thinking. These are subtle and elusive and hence easily escape a mode of inquiry that focuses on externally measurable outcomes. We illustrate how a sufficiently trained introspective approach can become a radar for facets of thinking that have found hardly any recognition in the literature so far. We consider this an important complement to third-person research because these introspective observations not only allow for new insights into the nature of thinking proper but also cast other psychological phenomena in a new light, for instance, attention and the self. We outline and discuss our findings and also present a roadmap for the reader interested in studying these phenomena in detail.