Ricoeur defines attestation as the "assurance of being oneself acting and suffering" or as the "assurance - the credence and the trust - of existing in the mode of selfhood." In this dissertation I discuss the concept of attestation in Ricoeur's philosophy in relation to the main dimensions of the self: Capacities, personal identity, memory and otherness. I state that attestation is the key to the three dialectics of Ricoeur's hermeneutics of the self: The dialectic between reflection and analysis, the (...) dialectic between idem-identity and ipse-identity and the dialectic between oneself and other. In these three dialectics, attestation, as the assurance of being oneself acting and suffering, allows the self to appropriate its otherness: The otherness of its capacities, the otherness of its identity, the otherness of its body, of other people and of its conscience. In other words, the self gains the confidence of being a self through the confidence that the actions it performs and the words it says are its own actions and words; the confidence that the narratives it tells express its own identity; the confidence that the body is its own body; the confidence that the esteem of others mediates its own esteem and that the values that it embraces are its own values. This analysis is made in the first four chapters of this dissertation. In the fifth chapter I explore the relationship between attestation and recognition. Attestation is not only necessary to understand the self at a hermeneutical level, but at the same time attestation shows a main ontological trait of the self: The self is attestation in the sense that the self is the confidence of existing as a self, confidence that is gained by appropriating its otherness. Thus, the concept of attestation along with providing an understanding of the self through otherness shows us that to become a self we need to attest to our self by appropriating our otherness. Then, as a conclusion, we can state that attestation serves as a bridge between hermeneutics and ontology in the philosophy of Paul Ricoeur. (shrink)