The evidence for consciousness is of roughly the same kind as for mystical experiences, i.e. verbal self-reports. There is no other evidence for either. Assume we're not conscious; what would you expect to be different? Obviously the part(s) of me that generate verbal reports (or other linguistic correspondence) seem to have access to other parts of my mind so that it seems like I'm a identity inside myself, but so what? What does consciousness itself add to any description of my experience?