This paper aims to discuss metacognition, which has especially been emphasized in recent years in relation to the subject of learning in the field of educational sciences, within various contexts. The method of this study, which presents a qualitative character, is the review of what has been obtained from the relevant literature both national and foreign. The study deals with the concepts of cognition and metacognition within various dimensions, and tries to describe them in the first place. Then, it analyzes these concepts in the contexts of the mind philosophy and the self psychology. The analyses focus on what the nature and source of the metacognitive capacity is and the characteristics of the relationship between cognition and metacognition and between metacognition and conscious. The study futher discusses, with a critical approach, whether a “metacognitive” capacity independent from “cognition” is really possible within the perspective of conscious. As a result of the study, it is seen that although there are numerous definitions of the concept of metacognition, there are not satisfactory explanations about the nature and source of the metacognitive capacity. It is identified that the relevant literature, generally experimental and monodisciplinary, focuses rather on the effects of the metacognitive capacity on learning and academic achievement, but not on what metacognition is and what it is not. The paper also concludes that in order for the metacognitive capacity to be comprehended together with its nature, source /sources, and all of its dimensions, there is a need for comprehensive analyses and discussions to be carried out with an interdisciplinary approach comprising such disciplines as psychology, neuropsychology, educational science, anthropology and philosophy.